Structure and architecture - OpenCourseWareocw.upj.ac.id/files/Textbook-ARS-205-TEXTBOOK-10-STRUKTUR-DA… · • ornamentation of structure • structure as ornament • structure

7.1 Introduction

Two related but distinct issues are discussed inthis chapter. These are the relationshipbetween structure and architecture and therelationship between structural engineers andarchitects. Each of these may take more thanone form, and the type which is in play at anytime influences the effect which structure hason architecture. These are issues which shedan interesting sidelight on the history ofarchitecture.

Structure and architecture may be related ina wide variety of ways ranging between theextremes of complete domination of thearchitecture by the structure to total disregardof structural requirements in the determinationof both the form of a building and of itsaesthetic treatment. This infinite number ofpossibilities is discussed here under six broadheadings:

• ornamentation of structure• structure as ornament• structure as architecture• structure as form generator• structure accepted• structure ignored.

As in the case of the relationship betweenstructure and architecture, the relationshipbetween architects and structural engineersmay take a number of forms. This may rangefrom, at one extreme, a situation in which theform of a building is determined solely by thearchitect with the engineer being concernedonly with making it stand up, to, at the otherextreme, the engineer acting as architect anddetermining the form of the building and all

other architectural aspects of the design. Mid-way between these extremes is the situation inwhich architect and engineer collaborate fullyover the form of a building and evolve thedesign jointly. As will be seen, the type ofrelationship which is adopted has a significanteffect on the nature of the resultingarchitecture.

7.2 The types of relationshipbetween structure and architecture

7.2.1 Ornamentation of structureThere have been a number of periods in thehistory of Western architecture in which theformal logic of a favoured structural systemhas been allowed to influence, if not totallydetermine, the overall form of the buildingsinto which the age has poured itsarchitectural creativity. In the periods inwhich this mood has prevailed, the forms thathave been adopted have been logicalconsequences of the structural armatures ofbuildings. The category ornamentation ofstructure, in which the building consists oflittle more than a visible structural armatureadjusted in fairly minor ways for visualreasons, has been one version of this.

Perhaps the most celebrated building in theWestern architectural tradition in whichstructure dictated form was the Parthenon inAthens (Fig. 7.1). The architecture of theParthenon is tectonic: structural requirementsdictated the form and, although the purpose ofthe building was not to celebrate structuraltechnology, its formal logic was celebrated aspart of the visual expression. The Doric Order,which reached its greatest degree of 73

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refinement in this building, was a system ofornamentation evolved from the post-and-beam structural arrangement.

There was, of course, much more to thearchitecture of the Greek temple thanornamentation of a constructional system. Thearchetypal form of the buildings and thevocabulary and grammar of the ornamentationhave had a host of symbolic meaningsattributed to them by later commentators1. Noattempt was made, however, by the builders ofthe Greek temples, either to disguise thestructure or to adopt forms other than thosewhich could be fashioned in a logical andstraightforward manner from the availablematerials. In these buildings the structure and

the architectural expression co-exist in perfectharmony.

The same may be said of the major buildingsof the mediaeval Gothic period (see Fig. 3.1),which are also examples of the relationshipbetween structure and architecture that may bedescribed as ornamentation of structure. Like theGreek temples the largest of the Gothic buildingswere constructed almost entirely in masonry, butunlike the Greek temples they had spaciousinteriors which involved large horizontal roofspans. These could only be achieved in masonryby the use of compressive form-active vaults. Theinteriors were also lofty, which meant that thevaulted ceilings imposed horizontal thrust on thetops of high flanking walls and subjected them tobending moment as well as to axial internal force.The walls of these Gothic structures weretherefore semi-form-active elements (see Section4.2) carrying a combination of compressive-axial

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Fig. 7.1 The Parthenon, Athens, 5th century BC. Structure and architecture perfectly united.

1 For example, Scully, V., The Earth, the Temple and the Gods,Yale University Press, New Haven, 1979.

and bending-type internal force. The archetypicalGothic arrangement of buttresses, flyingbuttresses and finials is a spectacular example ofa semi-form-active structure with ‘improved’cross-section and profile. Virtually everythingwhich is visible is structural and entirely justifiedon technical grounds. All elements were adjustedso as to be visually satisfactory: the ‘cabling’ ofcolumns, the provision of capitals on columnsand of string courses in walls and several othertypes of ornament were not essential structurally.

The strategy of ornamentation of structure,which was so successfully used in Greekantiquity and in the Gothic period, virtuallydisappeared from Western architecture at thetime of the Italian Renaissance. There wereseveral causes of this (see Section 7.3), one ofwhich was that the structural armatures ofbuildings were increasingly concealed behindforms of ornamentation which were notdirectly related to structural function. Forexample, the pilasters and half columns ofPalladio’s Palazzo Valmarana (Fig. 7.2) andmany other buildings of the period were notpositioned at locations which wereparticularly significant structurally. Theyformed part of a loadbearing wall in which allparts contributed equally to the load carryingfunction. Such disconnection of ornamentfrom structural function led to the structuraland aesthetic agendas drifting apart and hada profound effect on the type of relationshipwhich developed between architects andthose who were responsible for the technicalaspects of the design of buildings (seeSection 7.3).

It was not until the twentieth century, whenarchitects once again became interested intectonics (i.e. the making of architecture out ofthose fundamental parts of a buildingresponsible for holding it up) and in theaesthetic possibilities of the new structuraltechnologies of steel and reinforced concrete,that the ornamental use of exposed structurere-appeared in the architectural mainstream ofWestern architecture. It made its tentative firstappearance in the works of early Modernistssuch as Auguste Perret and Peter Behrens (Fig.7.3) and was also seen in the architecture of

Ludwig Mies van der Rohe. The structure ofthe Farnsworth House, for example, is exposedand forms a significant visual element. It wasalso adjusted slightly for visual reasons and inthat sense is an example of ornamentation ofstructure. Other more recent examples of suchvisual adjustments occurred in British HighTech. The exposed-steel structure of the

Structure and architecture

Fig. 7.2 The Palazzo Valmarana, Vicenza, by AndreaPalladio. The pilasters on this façade have their origins ina structural function but here form the outer skin of astructural wall. The architectural interest of the buildingdoes not lie in its structural make-up, however.

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Reliance Controls building at Swindon, UK(Fig. 7.4), for example, by Team 4 and TonyHunt, is a fairly straightforward technicalresponse to the problems posed by theprogrammatic requirements of the buildingand stands up well to technical criticism2. It isnevertheless an example of ornamentation ofstructure rather than a work of pureengineering because it was adjusted in minorways to improve its appearance. The H-sectionUniversal Column3 which was selected for its

very slender purlins, for example, was lessefficient as a bending element than the I-section Universal Beam would have been. Itwas used because it was considered that thetapered flanges of the Universal Beam wereless satisfactory visually than the parallel-sided flanges of the Universal Column in thisstrictly rectilinear building.

The train shed of the International RailTerminal at Waterloo station in London (Fig.7.17) is another example. The overallconfiguration of the steel structure, whichforms the principal architectural element ofthis building, was determined from technicalconsiderations. The visual aspects of thedesign were carefully controlled, however, andthe design evolved through very closecollaboration between the teams of architectsand engineers from the offices of Nicholas


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Fig. 7.3 AEG Turbine Hall, Berlin, 1908; Peter Behrens, architect. Glass and structure alternate on the side walls of thisbuilding and the rhythm of the steel structure forms a significant component of the visual vocabulary. Unlike in manylater buildings of the Modern Movement the structure was used ‘honestly’; it was not modified significantly for purelyvisual effect. With the exception of the hinges at the bases of the columns it was also protected within the externalweathertight skin of the building. (Photo: A. Macdonald)

2 See Macdonald, Angus J., Anthony Hunt, ThomasTelford, London, 2000.

3 The Universal Column and Universal Beam are thenames of standard ranges of cross-sections for hot-rolled steel elements which are produced by the Britishsteel industry.

Grimshaw and Partners and Anthony HuntAssociates so that it performed wellaesthetically as well as technically.

These few examples serve to illustrate thatthroughout the entire span of the history ofWestern architecture from the temples of Greekantiquity to late-twentieth-century structuressuch as the Waterloo Terminal, buildings havebeen created in which architecture has beenmade from exposed structure. The architects ofsuch buildings have paid due regard to therequirements of the structural technology andhave reflected this in the basic forms of thebuildings. The architecture has therefore beenaffected in a quite fundamental way by thestructural technology involved. At the sametime the architects have not allowedtechnological considerations to inhibit theirarchitectural imagination. The results have

been well-resolved buildings which performwell when judged by either technical or non-technical criteria.

7.2.2 Structure as ornament

‘The engineer’s aesthetic4 and architecture –two things that march together and followone from the other.’5

The relationship between structure andarchitecture categorised here as structure asornament involves the manipulation ofstructural elements by criteria which are

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Fig. 7.4 Reliance Controls building, Swindon, UK, 1966; Team 4, architects; Tony Hunt, structural engineer. The exposedstructure of the Reliance Controls building formed an important part of the visual vocabulary. It was modified in minorways to improve its appearance. (Photo: Anthony Hunt Associates)

4 Author’s italics.5 Le Corbusier, Towards a New Architecture, Architectural

Press, London, 1927.

principally visual and it is a relationship whichhas been largely a twentieth-centuryphenomenon. As in the category ornamentationof structure the structure is given visualprominence but unlike in ornamentation ofstructure, the design process is driven by visualrather than by technical considerations. As aconsequence the performance of thesestructures is often less than ideal when judgedby technical criteria. This is the feature whichdistinguishes structure as ornament fromornamentation of structure.

Three versions of structure as ornament maybe distinguished. In the first of these,structure is used symbolically. In this scenariothe devices which are associated withstructural efficiency (see Chapter 4), which aremostly borrowed from the aerospace industryand from science fiction, are used as a visualvocabulary which is intended to convey theidea of progress and of a future dominated bytechnology. The images associated withadvanced technology are manipulated freely toproduce an architecture which celebratestechnology. Often, the context is inappropriateand the resulting structures perform badly in atechnical sense.

In the second version, spectacular exposedstructure may be devised in response toartificially created circumstances. In this type ofbuilding, the forms of the exposed structureare justified technically, but only as thesolutions to unnecessary technical problemsthat have been created by the designers of thebuilding.

A third category of structure as ornamentinvolves the adoption of an approach in whichstructure is expressed so as to produce areadable building in which technology iscelebrated, but in which a visual agenda is pursuedwhich is incompatible with structural logic. The lack ofthe overt use of images associated withadvanced technology distinguishes this fromthe first category.

Where structure is used symbolically, avisual vocabulary which has its origins in thedesign of lightweight structural elements – forexample the I-shaped cross-section, thetriangulated girder, the circular hole cut in the

web, etc. (see Chapter 4) – is usedarchitecturally to symbolise technicalexcellence and to celebrate state-of-the-arttechnology. Much, though by no means all, ofthe architecture of British High Tech falls intothis category. The entrance canopy of theLloyds headquarters building in London is anexample (Fig. 7.5). The curved steel elementswhich form the structure of this canopy, withtheir circular ‘lightening’ holes (holes cut outto lighten the element – see Section 4.3) arereminiscent of the principal fuselage elementsin aircraft structures (Fig. 4.14). Thecomplexity of the arrangement is fully justifiedin the aeronautical context where saving ofweight is critical. The use of lightweightstructures in the canopy at Lloyds merelyincreases the probability that it will be blownaway by the wind. Its use here is entirelysymbolic.

The Renault Headquarters building inSwindon, UK, by Foster Associates and OveArup and Partners is another example of thisapproach (see Figs 3.19 and 6.8). The structureof this building is spectacular and a keycomponent of the building’s image, which isintended to convey the idea of a company witha serious commitment to ‘quality design’6 andan established position at the cutting edge oftechnology. The building is undoubtedlyelegant and it received much critical acclaimwhen it was completed; these designobjectives were therefore achieved. BernardHanon, President-Directeur General, RégieNationale des Usines Renault, on his first visitfelt moved to declare: ‘It’s a cathedral.’7.

The structure of the Renault building doesnot, however, stand up well to technicalcriticism. It consists of a steel-framesupporting a non-structural envelope. Thebasic form of the structure is of multi-bayportal frames running in two principaldirections. These have many of the featuresassociated with structural efficiency: the


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6 Lambot, I. (Ed.), Norman Foster: Foster Associates: Buildingsand Projects, Vol. 2, Watermark, Hong Kong, 1989.

7 Ibid.

longitudinal profile of each frame is matchedto the bending-moment diagram for theprincipal load; the structure is trussed (i.e.separate compression and tensile elements areprovided); the compressive elements, whichmust have some resistance to bending, havefurther improvements in the form of I-shapedcross-sections and circular holes cut into thewebs. Although these features improve theefficiency of the structure, most of them arenot justified given the relatively short spansinvolved (see Chapter 6). The structure isunnecessarily complicated and there is nodoubt that a conventional portal-framearrangement (a primary/secondary structuralsystem with the portals serving as the primarystructure, as in the earlier building by FosterAssociates at Thamesmead, London (see Fig.1.5)), would have provided a more economicalstructure for this building. Such a solution wasrejected at the outset of the project by theclient on the grounds that it would not haveprovided an appropriate image for thecompany8. The decision to use the moreexpensive, more spectacular structure wastherefore taken on stylistic grounds.

The structure possesses a number of otherfeatures which may be criticised from a technicalpoint of view. One of these is the placing of asignificant part of it outside the weathertightenvelope, which has serious implications fordurability and maintenance. The configuration ofthe main structural elements is also far fromideal. The truss arrangement cannot toleratereversal of load because this would place thevery slender tension elements into compression.As designed, the structure is capable of resistingonly downward-acting gravitational loads andnot uplift. Reversal of load may tend to occur inflat-roofed buildings, however, due to the highsuction forces which wind can generate.Thickening of the tensile elements to give themthe capability to resist compression wasconsidered by the architect to be unacceptablevisually9 and so this problem was solved by

specifying heavier roof cladding than originallyintended (or indeed required) so that no reversalof load would occur. Thus the whole structurewas subjected, on a permanent basis, to a largergravitational load than was strictly necessary. Afurther observation which might be maderegarding the structure of this building is thatthe imagery employed is not particularly ‘cuttingedge’, much of it having been evolved in the 79


Fig. 7.5 Entrance canopy, Lloyds headquarters building,London, UK, 1986; Richard Rogers and Partners, architects;Ove Arup & Partners, structural engineers. The curved steelribs with circular ‘lightening’ holes are reminiscent ofstructures found in the aerospace industry. (Photo: ColinMcWilliam)

8 Ibid.9 See Lambot, ibid.

earliest days of iron and steel frame design inthe nineteenth century.

The sources of the visual vocabulary ofstructural technology used in the symbolicversion of structure as ornament are various and,for the most part, not architectural. In somecases the source has been science fiction. Moreusually, images were employed which wereperceived to represent very advancedtechnology, the most fruitful source for thelatter being aeronautical engineering where thesaving of weight is of paramount importance,and particularly the element with complex‘improved’ cross-section and circular ‘lightening’holes. Forms and element types which areassociated with high structural efficiency – seeChapter 4 – are therefore employed.

One of the problems facing the designers ofaircraft or vehicle structures is that the overallform is dictated by non-structuralconsiderations. The adoption of structurallyefficient form-active shapes is not possible andhigh efficiency has to be achieved byemploying the techniques of ‘improvement’.The whole vocabulary of techniques of‘improvement’ – stressed-skin monocoque andsemi-monocoque ‘improved’ beams, internaltriangulation, sub-elements with I-shapedcross-sections, tapered profiles and circular‘lightening’ holes – is exploited in these fieldsto achieve acceptable levels of efficiency (seeFigs 4.13 to 4.15). It is principally thisvocabulary which has been adopted byarchitects seeking to make a symbolic use ofstructure and which has often been applied insituations where the span or loading would notjustify the use of complicated structures of thistype on technical grounds alone.

The dichotomy between the appearance andthe reality of technical excellence is nowheremore apparent than in the works of the architectsof the ‘Future Systems’ group (Fig. 7.6):

‘Future Systems believes that borrowingtechnology developed from structuresdesigned to travel across land(automotive), or through water (marine),air (aviation) or vacuum (space) can helpto give energy to the spirit of architecture

by introducing a new generation ofbuildings which are efficient, elegant,versatile and exciting. This approach toshaping the future of architecture is basedon the celebration of technology, not theconcealment of it.’10


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10 Jan Kaplicky and David Nixon of Future Systems quotedin the final chapter of Wilkinson, C., Supersheds,Butterworth Architecture, Oxford, 1991. Later in thesame statement Kaplicky and Nixon declare, of thetechnology of vehicle and aerospace engineering, ‘It istechnology which is capable of yielding an architectureof sleek surfaces and slender forms – an architecture ofefficiency and elegance, and even excitement.’ It isclear from this quotation that it is the appearancerather than the technical reality which is attractive toKaplicky and Nixon.

Fig. 7.6 Green Building (project), 1990: Future Systems,architects. Technology transfer or technical image-making?Many technical criticisms could be made of this design.The elevation of the building above ground level isperhaps the most obvious as this requires that anelaborate structural system be adopted including floorstructures of steel-plate box-girders similar to those whichare used in long-span bridge construction. There is notechnical justification for their use here where a moreenvironmentally friendly structural system, such asreinforced concrete slabs supported on a conventionalcolumn grid, would have been a more convincing choice.This would not have been so exciting visually, but it wouldhave been more convincing in the context of the idea of asustainable architecture.

The quotation reveals a degree of naivetyconcerning the nature of technology. Itcontains the assumption that dissimilartechnologies have basic similarities whichproduce similar solutions to quite differenttypes of problem.

The ‘borrowing of technology’ referred to inthe quotation above from Future Systems isproblematic. Another name for this is‘technology transfer’, a phenomenon in whichadvanced technology which has beendeveloped in one field is adapted and modifiedfor another. Technology transfer is a conceptwhich is of very limited validity becausecomponents and systems which are developedfor advanced technical applications, such asoccur in the aerospace industry, are designedto meet very specific combinations ofrequirements. Unless very similarcombinations occur in the field to which thetechnology is transferred it is unlikely that theresults will be satisfactory from a technologicalpoint of view. Such transfer is therefore alsomisleading symbolically on any level but themost simplistic.

The claims which are made for technologytransfer are largely spurious if judged bytechnical criteria concerned with function andefficiency. The reality of technology transfer toarchitecture is normally that it is the imageand appearance which is the attractive elementrather than the technology as such.

It is frequently stated by the protagonists ofthis kind of architecture11 that, because itappears to be advanced technically, it willprovide the solutions to the architecturalproblems posed by the worsening globalenvironmental situation. This is perhaps theirmost fallacious claim. The environmentalproblems caused by shortages of materials andenergy and by increasing levels of pollution arereal technical problems which require genuinetechnical solutions. Both the practice and theideology of the symbolic use of structure are

fundamentally incompatible with therequirements of a sustainable architecture. Themethodology of the symbolic use of structure,which is to a large extent a matter of borrowingimages and forms from other technical areaswithout seriously appraising their technicalsuitability, is incapable of addressing realtechnical problems of the type which are posedby the need for sustainability. The ideology isthat of Modernism which is committed to thebelief in technical progress and the continualdestruction and renewal of the builtenvironment12. This is a high-energy-consumption scenario which is not ecologicallysound.

The benefits of new technological solutionswould have to be much greater than at presentfor this approach to be useful. The forms of afuture sustainable architecture are more likely tobe evolved from the combination of innovativeenvironmental technology with traditionalbuilding forms, which are environmentallyfriendly because they are adapted to localclimatic conditions and are constructed indurable, locally available materials, than bytransferring technology from the extremelyenvironmentally unfriendly aerospace industry.

The second category of structure as ornamentinvolves an unnecessary structural problem,created either intentionally or unintentionally,which generates the need for a spectacularresponse. A good example of this is found inthe structure of the Centre Pompidou andconcerns the way in which the floor girders areconnected to the columns (Figs 7.7 and 6.7).

The rectangular cross-section of thisbuilding has three zones at every level (Fig.7.8). There is a central main space which isflanked by two peripheral zones: on one side ofthe building the peripheral zone is used for acirculation system of corridors and escalators;on the other it contains services. The architectschose to use the glass wall which formed thebuilding’s envelope to delineate these zones

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11 Chief amongst these is Richard Rogers and thearguments are set out in Rogers, Architecture, A ModernView, Thames and Hudson, London, 1991.

12 This is very well articulated by Charles Jencks in ‘TheNew Moderns’, AD Profile – New Architecture: The NewModerns and The Super Moderns, 1990.

and placed the services and circulation zonesoutside the envelope. The distinction ismirrored in the structural arrangement: themain structural frames, which consist oftriangulated girders spanning the central space,are linked to the perimeter columns throughcantilever brackets, named ‘gerberettes’ afterthe nineteenth-century bridge engineer

Heinrich Gerber, which are associated with theperipheral zones. The joints between thebrackets and the main frames coincide with thebuilding’s glass wall and the spatial andstructural zonings are therefore identical.

The elaborate gerberette brackets, which aremajor visual elements on the exterior of thebuilding, pivot around the hinges connecting


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Fig. 7.7 Gerberette brackets, Centre Pompidou, Paris,France, 1978; Piano and Rogers, architects; Ove Arup &Partners, structural engineers. The floor girders are attachedto the inner ends of these brackets, which pivot on hingepins through the columns. The weights of the floors arecounterbalanced by tie forces applied at the outer ends ofthe brackets. The arrangement sends 25% more force intothe columns than would occur if the floor beams wereattached to them directly. (Photo: A. Macdonald)

Fig. 7.8 Cross-section, Centre Pompidou, Paris, France, 1978; Piano and Rogers, architects; Ove Arup & Partners, structuralengineers. The building is subdivided into three principal zones at every level and the spatial and structural arrangementscorrespond. The main interior spaces occupy a central zone associated with the main floor girders. The gerberette bracketsdefine peripheral zones on either side of the building which are associated with circulation and services.

them to the columns (Fig. 7.7). The weights ofthe floors, which are supported on the inner endsof the brackets, are counterbalanced bydownward-acting reactions at the outer endsprovided by vertical tie rods linking them withthe foundations. This arrangement sends 25%more force into the columns at each level than isrequired to support the floors. The idea ofconnecting the floor girders to the columnsthrough these cantilevered brackets does nottherefore make a great deal of engineering sense.

Apart from the unnecessary overloading ofthe columns, the brackets themselves aresubjected to high levels of bending-type internalforce and their design presented an interesting,if unnecessary, challenge to the engineers. Therequired solution to this was to give the bracketsa highly complex geometry which reflected theirstructural function. The level of complexity couldonly be achieved by casting of the metal, and theidea of fabricating the brackets from cast steel, atechnique which was virtually unknown inarchitecture at the time, was both courageousand innovative. It allowed forms to be usedwhich were both expressive of the structuralfunction of the brackets and which made a moreefficient use of material than would haveoccurred had they been made from standardI-sections. According to Richard Rogers: ‘Wewere repeating the gerberette brackets over 200times and it was cheaper to use less steel than itwas to use an I-beam. That’s the argument onthat I would have thought’13.

Another advantage of casting was that itintroduced an element of hand crafting into thesteelwork. This was something of apreoccupation of Peter Rice, the principalstructural engineer on the project who, insomething of the tradition of the much earlierBritish Arts and Crafts Movement, believed thatmuch of the inhumanity of Modern architecturestemmed from the fact that it was composedentirely of machine-made components.

There were therefore several agendasinvolved, most of them concerned with visualrather than structural considerations, and

there is no doubt that the presence of theseunusual components on the exterior of thebuilding contributes greatly to its aestheticsuccess. Thus, the ingenious solution of anunnecessarily-created technical problem foundarchitectural expression. This is the essence ofthis version of structure as ornament. Its greatestexponent has perhaps been the Spanisharchitect/engineer Santiago Calatrava.

A third kind of architecture which involvesstructure of questionable technical validityoccurs in the context of a visual agenda that isincompatible with structural requirements. TheLloyds headquarters building (Fig. 7.9) in 83


13 Interview with the author, February 2000.

Fig. 7.9 Lloyds headquarters building, London, UK, 1986;Richard Rogers and Partners, architects; Ove Arup &Partners, structural engineers. The building has arectangular plan and six projecting service towers.

London, by the same designers who producedthe Centre Pompidou (Richard Rogers andPartners as architects and Ove Arup andPartners as structural engineers), is a goodexample of this.

Lloyds is a multi-storey office building witha rectangular plan (Fig. 7.10). The building hasa central atrium through most levels, whichconverts the floor plan into a rectangulardoughnut, and, as at the Centre Pompidou,services which are external to the building’senvelope. At Lloyds these are placed in aseries of towers which disguise therectilinearity of the building. There are alsoexternal ducts which grip the building like thetentacles of an octopus (Fig. 7.11). Thestructural armature is a reinforced concretebeam-and-column framework which supportsthe rectangular core of the building. This formsa prominent element of the visual vocabularybut is problematic technically.

The columns are located outside theperimeter of the floor structures which theysupport and this has the effect of increasingthe eccentricity with which load is applied tothe columns – a highly undesirableconsequence structurally. This solution wasadopted to make the structure ‘readable’ (acontinuing concern of Richard Rogers) byarticulating the different parts as separateidentifiable elements. It resulted in the floors


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Fig. 7.10 Plan, Lloyds headquartersbuilding, London, UK, 1986; RichardRogers and Partners, architects; Ove Arup& Partners, structural engineers. Thebuilding has a rectangular plan with acentral atrium. The structure is areinforced concrete beam-column framecarrying a one-way-spanning floor.

Fig. 7.11 Lloyds headquarters building, London, UK,1986; Richard Rogers and Partners, architects; Ove Arup &Partners, structural engineers. The service towers whichproject from the rectangular plan are one of the mostdistinctive features of the building.

being connected to the columns throughelaborate pre-cast concrete brackets (Fig. 7.12).In this respect the Lloyds building is similar tothe Centre Pompidou. An architectural idea,‘readability’, created a problem which requireda structural response. The pre-cast columnjunctions were less spectacular than thegerberettes of the Centre Pompidou, but hadan equivalent function, both technically andvisually.

There are, however, important differencesbetween Pompidou and Lloyds which placethem in slightly different categories so far asthe relationship between structure andarchitecture is concerned. At Lloyds, the logicof readability was abandoned in the treatmentof the underside of the exposed reinforcedconcrete floors. These take the shape of arectangular doughnut in plan due to thepresence of the central atrium. Structurally,they consist of primary beams, spanningbetween columns at the perimeter and withinthe atrium, which support a ribbed one-way-spanning floor system. For purely visualreasons the presence of the primary beamswas suppressed and they were concealed bythe square grid of the floor structure. Theimpression thus given is that the floors are atwo-way-spanning system supported directlyon the columns without primary beams. Greatingenuity was required on the part of thestructural engineering team to produce astructure which had a satisfactory technicalperformance while at the same time appearingto be that which it was not.

This task was not made easier by anothervisual requirement, namely that the ribs of thefloor structure should appear to be parallel-sided rather than tapered. A small amount oftaper was in fact essential to allow theformwork to be extracted, but to make the ribsappear to be parallel-sided the taper wasupwards rather than downwards. This meantthat the formwork had to be taken out fromabove which eliminated the possibility ofcontinuity between the ribs and the floor slabwhich they support. The benefits of compositeaction between the ribs and the floor slab,which normally greatly increases the efficiency

of reinforced concrete floors, were thusforegone. The design of this structure wastherefore driven almost entirely by visualconsiderations and a heavy penalty was paid interms of structural efficiency. 85


Fig. 7.12 Atrium, Lloyds headquarters building, London,UK, 1986; Richard Rogers and Partners, architects; OveArup & Partners, structural engineers. The columns are setoutside the perimeter of the floor decks and connected tothem through visually prominent pre-cast concretebrackets. The arrangement allows the structure to be easily‘read’ but is far from ideal structurally. It introducesbending into the columns, which causes highconcentrations of stress at the junctions.

The conclusion which may be drawn fromthe above examples of structure as ornament isthat in many buildings with exposed structuresthe structure is technically flawed despiteappearing visually interesting. This does notmean that the architects and engineers whodesigned these buildings were incompetent orthat the buildings themselves are examples ofbad architecture. It does mean, however, thatin much architecture in which exposedstructure is used to convey the idea oftechnical excellence (most of High-Techarchitecture falls into this category), the formsand visual devices which have been employedare not themselves examples of technologywhich is appropriate to the function involved.It will remain to be seen whether thesebuildings stand the test of time, eitherphysically or intellectually: the ultimate fate ofmany of them, despite their enjoyablequalities, may be that of the discarded toy.

7.2.3 Structure as architecture

7.2.3.1 IntroductionThere have always been buildings whichconsisted of structure and only structure. Theigloo and the tepee (see Figs 1.2 and 1.3) areexamples and such buildings have, of course,existed throughout history and much of humanpre-history. In the world of architectural historyand criticism they are considered to be‘vernacular’ rather than ‘architecture’.Occasionally, they have found their way intothe architectural discourse and where this hasoccurred it has often been due to the very largescale of the particular example. Examples arethe Crystal Palace (Fig. 7.25) in the nineteenthcentury and the CNIT building (see Fig. 1.4) inthe twentieth. These were buildings in whichthe limits of what was technically feasible wereapproached and in which no compromise withstructural requirements was possible. This is athird type of relationship between structureand architecture which might be referred to asstructure without ornament, but perhaps evenmore accurately as structure as architecture.

The limits of what is possible structurallyare reached in the obvious cases of very long

spans and tall buildings. Other cases are thosein which extreme lightness is desirable, forexample because the building is required to beportable, or where some other technical issueis so important that it dictates the designprogramme.

7.2.3.2 The very long spanIt is necessary to begin a discussion on long-span structures by asking the question: whenis a span a long span? The answer offered herewill be: when, as a consequence of the size ofthe span, technical considerations are placedso high on the list of architectural prioritiesthat they significantly affect the aesthetictreatment of the building. As has already beendiscussed in Chapter 6, the technical problemposed by the long span is that of maintaining areasonable balance between the load carriedand the self-weight of the structure. The formsof longest-span structures are therefore thoseof the most efficient structure types, namelythe form-active types such as the compressivevault and the tensile membrane, and the non-or semi-form-active types into whichsignificant ‘improvements’ have beenincorporated.

In the pre-industrial age the structural formwhich was used for the widest spans was themasonry vault or the dome. The only otherstructural material available in the pre-industrial age was timber. Due to the smallsize of individual timbers, any large woodenstructure involved the joining together of manyelements, and making joints in timber whichhad satisfactory structural performance wasdifficult. In the absence of a satisfactoryjointing technology, large-scale structures intimber were not feasible in the pre-Modernworld. Also, the understanding of how toproduce efficient fully-triangulated trusses didnot occur until the nineteenth century.

The development of reinforced concrete inthe late nineteenth century allowed theextension of the maximum span which waspossible with the compressive form-active typeof structure. Reinforced concrete has a numberof advantages over masonry, the principal onebeing its capability to resist tension as well as


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compression and its consequent ability toresist bending. The vault and the dome are, ofcourse, compressive form-active structures, butthis does not mean that they are neversubjected to bending moment because theform-active shape is only valid for a specificload pattern. Structures which supportbuildings are subjected to variations in theload pattern, with the result that compressiveform-active structures will in somecircumstances become semi-form-active andbe required to resist bending. If the structuralmaterial has little tensile strength, as is thecase with masonry, its cross-section must besufficiently thick to prevent the tensile bendingstress from exceeding the compressive axialstress which is also present. Masonry vaultsand domes must therefore be fairly thick andthis compromises their efficiency. Anadditional complication with the use of thedome is that tensile stresses can develop inthe circumferential direction near the base ofthe structure with the result that cracksdevelop. Most masonry domes are in factreinforced to a limited extent with metal –usually in the form of iron bars – to counteractthis tendency.

Because reinforced concrete can resist bothtensile and bending stress, compressive form-active structures in this material can be madevery much thinner than those in masonry. Thisallows greater efficiency, and therefore greaterspans, to be achieved because the principalload on a dome or vault is the weight of thestructure itself.

Another advantage of reinforced concrete isthat it makes easier the adoption of ‘improved’cross-sections. This technique has been usedwith masonry domes, however, the twin skinsof Brunelleschi’s dome for Florence Cathedral(Fig. 7.13)14 being an example, but the

mouldability of reinforced concrete greatlyextended this potential for increasing theefficiency with which a dome or vault can resistbending moment caused by semi-form-activeload patterns.

Among the earliest examples of the use ofreinforced concrete for vaulting on a largescale are the airship hangars for Orly Airport in 87


14 The twin skin arrangement may not have been adoptedfor structural reasons. An interesting speculation iswhether Brunelleschi, who was a brilliant technologist,may have had an intuitive understanding of theimproved structural performance which results from atwo-skin arrangement.

Fig. 7.13 Dome of the cathedral, Florence, Italy, 1420–36;Brunelleschi. The dome of the cathedral at Florence is asemi-form-active structure. The brickwork masonryenvelope has an ‘improved’ cross-section and consists ofinner and outer skins linked by diaphragms. An ingeniouspattern of brickwork bonding was adopted to ensuresatisfactory composite action. Given the span involved,and certain other constraints such as that the dome had tosit on an octagonal drum, it is difficult to imagine anyother form which would have been feasible structurally.This memorable work of architecture is therefore anexample of genuine ‘high tech’. The overall form wasdetermined from structural considerations and notcompromised for visual effect. (Drawing: R. J. Mainstone)

Paris by Eugène Freyssinet (Fig. 7.14). Acorrugated cross-section was used in thesebuildings to improve the bending resistance ofthe vaults. Other masters of this type of

structure in the twentieth century were PierLuigi Nervi, Eduardo Torroja and FélixCandela. Nervi’s structures (Fig. 7.15) areespecially interesting because he developed asystem of construction which involved the useof pre-cast permanent formwork in ferro-cement, a type of concrete made from very fineaggregate and which could be moulded intoextremely slender and delicate shapes. Theelimination of much of the temporaryformwork and the ease with which the ferro-cement could be moulded into ‘improved’cross-sections of complex geometry, allowedlong-span structures of great sophistication tobe built relatively economically. The finaldome or vault consisted of a compositestructure of in-situ concrete and ferro-cementformwork.

Other notable examples of twentieth-century compressive form-active structures arethe CNIT building in Paris by Nicolas Esquillan(see Fig. 1.4) and the roof of the SmithfieldPoultry Market in London by R. S. Jenkins ofOve Arup and Partners (Fig. 7.16).

Compressive form-active structures are alsoproduced in metal, usually in the form oflattice arches or vaults, to achieve very longspans. Some of the most spectacular of theseare also among the earliest, the train shed atSt Pancras Station in London (1868) byWilliam Barlow and R. M. Ordish (span 73 m)(Fig. 7.51) and the structure of the Galerie desMachines for the Paris Exhibition of 1889, byContamin and Dutert (span 114 m) beingnotable examples. The subject has been wellreviewed by Wilkinson15. This traditioncontinues in the present day and notablerecent examples are the International RailTerminal at Waterloo Station, London, byNicholas Grimshaw & Partners with YRMAnthony Hunt Associates (Fig. 7.17) and thedesign for the Kansai Airport building forOsaka, Japan by Renzo Piano with Ove Arupand Partners.

Cable-network structures are another groupwhose appearance is distinctive because


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Fig. 7.14 Airship Hangars, Orly Airport, France, 1921;Eugène Freyssinet, structural engineer. The skin of thiscompressive form-active vault has a corrugated cross-section which allows efficient resistance to secondarybending moment. The form adopted was fully justifiedgiven the span involved and was almost entirelydetermined from structural considerations.

Fig. 7.15 Palazzetto dello Sport, Rome, Italy, 1960; PierLuigi Nervi, architect/engineer. This is another example ofa building with a form determined solely from structuralrequirements. The compressive form-active dome is acomposite of in situ and pre-cast reinforced concrete andhas an ‘improved’ corrugated cross-section. (Photo: BritishCement Association)

15 Op. cit.

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Fig. 7.16 Smithfield Poultry Market,London, UK; Ove Arup & Partners,structural engineers. The architecture hereis dominated by the semi-form-active shellstructure which forms the roof of thebuilding. Its adoption was justified by thespan of around 60 m. The ellipticalparaboloid shape was selected rather thana fully form-active geometry because itcould be easily described mathematically,which simplified both the design and theconstruction. (Photo: John Maltby Ltd)

Fig. 7.17 International Rail Terminal, Waterloo Station, London, UK, 1992; Nicholas Grimshaw & Partners, architects;YRM Anthony Hunt Associates, structural engineers. This building is part of a continuing tradition of long-span structuresfor railway stations. The design contains a number of innovatory features, most notably the use of tapering steel sub-elements. (Photo: J. Reid and J. Peck)

technical considerations have been allocated avery high priority, due to the need to achieve along span or a very lightweight structure. Theyare tensile form-active structures in which avery high level of efficiency is achieved. Theirprincipal application has been as the roofstructures for large single-volume buildingssuch as sports arenas. The ice hockey arena atYale by Eero Saarinen (Fig. 7.18) and the cable-network structures of Frei Otto (see Fig. i) aretypical examples.

In these buildings the roof envelope is ananticlastic double-curved surface16: twoopposite curvatures exist at every location. Thesurface is formed by two sets of cables, oneconforming to each of the constituentdirections of curvature, an arrangement whichallows the cables to be pre-stressed against

each other. The opposing directions ofcurvature give the structure the ability totolerate reversals of load (necessary to resistwind loading without gross distortion inshape) and the pre-stressing enablesminimisation of the movement which occursunder variations in load (necessary to preventdamage to the roof cladding).

In the 1990s, a new generation of mast-supported synclastic cable networks wasdeveloped. The principal advantage of theseover the earlier anticlastic forms was that, dueto the greater simplicity of the form, themanufacture of the cladding was made easier.

The Millennium Dome in London (Fig. 7.19),which is not of course a dome in the structuralsense, is perhaps the best known of these. Inthis building a dome-shaped cable network issupported on a ring of 24 masts. The overalldiameter of the building is 358 m but themaximum span is approximately 225 m, whichis the diameter of the ring described by the 24masts. The size of the span makes the use of acomplex form-active structure entirely justified.The cable network to which the cladding isattached consists of a series of radial cables, inpairs, which span 25 m between nodessupported by hanger cables connecting themto the tops of the masts. The nodes are alsoconnected by circumferential cables whichprovide stability. The downward curving radialcables are pre-stressed against the hangercables and this makes them almost straightand converts the surface of the dome into aseries of facetted panels. It is thischaracteristic which simplifies the fabricationof the cladding. In fact, being tensile form-active elements, the radial cables are slightlycurved, and this curvature had to be allowedfor in the design of the cladding, but theoverall geometry is nevertheless considerablyless complex than an anticlastic surface. Thecladding fabric of the Millennium Dome isPTFE-coated glass fibre.

The few examples of cable networksillustrated here demonstrate that, althoughthis type of structure is truly form-active with ashape which is dependent on the pattern ofapplied load, the designer can exert


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16 The terms anticlastic and synclastic describe differentfamilies of curved surface. An anticlastic surface isdescribed by two sets of curves acting in oppositedirections. The canopy of the Olympic stadium atMunich (Fig. i) is an example. Synclastic surfaces arealso doubly curved but with the describing curvesacting in the same direction. The shell roof of theSmithfield Poultry market (Fig. 7.16) is an example ofthis type.

Fig. 7.18 David S. Ingalls ice hockey rink, Yale, USA,1959; Eero Saarinen, architect; Fred Severud, structuralengineer. A combination of compressive form-active archesand a tensile form-active cable network was used in thislong-span building. The architecture is totally dominatedby the structural form.

considerable influence on the overall formthrough the choice of support conditions andsurface type. The cable network can besupported either on a configuration of semi-form-active arches or on a series of masts; itcan also be either synclastic or anticlastic andthe configurations which are adopted for theseinfluence the overall appearance of thebuilding.

Judged by the criteria outlined in Section6.3, most of the form-active vaulted and cablestructures are not without technicalshortcomings. They are difficult to design andbuild and, due to their low mass, provide poorthermal barriers. In addition, the durability ofthese structures, especially the cable networks,is lower than that of most conventionalbuilding envelopes. Acceptance of thesedeficiencies is justified, however, in theinterests of achieving the high levels ofstructural efficiency required to produce large

spans. In the cases described here thecompromise which has been reached issatisfactory, given the spans involved and theuses for which the buildings were designed.

All of the long-span buildings consideredhere may therefore be regarded as true ‘high-tech’ architecture. They are state-of-the-artexamples of structural technology employed toachieve some of the largest span enclosures inexistence. The technology employed wasnecessary to achieve the spans involved andthe resulting forms have been given minimalstylistic treatment.

7.2.3.3 Very tall buildingsIn the search for the truly high-tech building,which is another way of thinking of thecategory structure as architecture, the skyscraper isworthy of careful consideration. From astructural point of view two problems areposed by the very high building: one is the 91


Fig. 7.19 Millennium Dome, London, UK, 1999; Richard Rogers and Partners, architects; Buro Happold, structuralengineers. This is mast-supported, dome-shaped cable network with a diameter of 358 m. The use of a tensile form-activestructure is fully justified for structures of this size.

provision of adequate vertical support and theother is the difficulty of resisting high lateralloading, including the dynamic effect of wind.So far as vertical support is concerned, thestrength required of the columns or walls isgreatest at the base of the building, where theneed for an excessively large volume ofstructure is a potential problem. In the daysbefore the introduction of iron and steel thiswas a genuine difficulty which placed a limiton the possible height of structures. Theproblem was solved by the introduction ofsteel framing. Columns are loaded axially, andso long as the storey height is low enough tomaintain the slenderness ratio17 at areasonably low level and thus inhibit buckling,the strength of the material is such thatexcessive volume of structure does not occurwithin the maximum practical height limitsimposed by other, non-structural constraints.

The need to increase the level of verticalsupport towards the base of a tall building hasrarely been expressed architecturally. In manyskyscrapers the apparent size of the verticalstructure – the columns and walls – is identicalthroughout the entire height of the building.There have, of course, been many technicalinnovations in connection with aspects of thesupport of gravitational load in high buildings.In particular, as was pointed out byBillington18, changes in the relationshipbetween the vertical and horizontal structuralelements have led to the creation of largercolumn-free spaces in the interiors. Theseinnovations have, however, found very limitedarchitectural expression.

The need to accommodate wind loadingas opposed to gravitational loads has had agreater effect on the aesthetics of very tallbuildings. As with vertical support elements,in the majority of skyscrapers the architecthas been able to choose not to express the


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17 See Macdonald, Angus J., Structural Design for Architecture,Architectural Press, Oxford, 1997, Appendix 2, for anexplanation of slenderness ratio.

18 Billington, D. P., The Tower and the Bridge, Basic Books,New York, 1983.

Fig. 7.20 World Trade Centre, New York, USA, 1973;Minoru Yamasaki, architect; Skilling, Helle, Christiansen &Robertson, structural engineers. The closely-spacedcolumns on the exteriors of these buildings are structuraland form a ‘framed-tube’ which provides efficient resistanceto lateral load. In response to lateral load the building actsas a vertical cantilever with a hollow box cross-section. Thisis an example of a structural system, not compromised forvisual reasons, exerting a major influence on theappearance of the building. (Photo: R. J. Mainstone)

bracing structure so that, although many ofthese buildings are innovative in a structuralsense, this is not visually obvious. The verytallest buildings, however, have beendesigned to behave as single verticalcantilevers with the structure concentratedon the exterior; in these cases theexpression of the structural action wasunavoidable.

The framed- and trussed-tubeconfigurations19 (Figs 7.20 and 7.21) areexamples of structural arrangements whichallow tall buildings to behave as vertical

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19 See Schueller, W., High Rise Building Structures, JohnWiley, London, 1977, for an explanation of bracingsystems for very tall buildings.

Fig. 7.21 John Hancock Building, Chicago,USA, 1969; Skidmore, Owings and Merrill,architects and structural engineers. Thetrussed-tube structure here forms a majorcomponent of the visual vocabulary. (Photo:Chris Smallwood)

cantilevers in response to wind loads. In bothcases the building is treated as a hollow tube,a non-form-active element with an ‘improved’cross-section, in its resistance to lateralloading. The tube is formed by concentratingthe vertical structure at the perimeter of theplan. The floors span from this to a centralservices core which provides vertical supportbut does not normally contribute to theresistance of wind load.

Such buildings are usually given a squareplan. With the wind blowing parallel to one ofthe faces, the columns on the windward andleeward walls act as tensile and compressionflanges respectively of the cantilever cross-section, while the two remaining external wallsform a shear link between these. In the case ofthe framed tube, of which the World TradeCentre buildings in New York by MinoruYamasaki (Fig. 7.20) are examples, the shear


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Fig. 7.22 Sears Tower,Chicago, USA, 1974;Skidmore, Owings andMerrill, architects andstructural engineers. Thisbuilding, which is currentlythe tallest in the world, issubdivided internally by acruciform arrangement of‘walls’ of closely spacedcolumns which enhance itsresistance to wind loading.This structural layout isexpressed in the exteriorform.

connection is provided by rigid frame actionbetween the columns and the very short beamswhich link them. In trussed-tube structures,such as the John Hancock Building in Chicagoby Skidmore, Owings and Merrill (Fig. 7.21),the shear connection is provided by diagonalbracing elements. Because in each of thesecases the special structural configurationwhich was adopted to provide resistance tolateral load resulted in the structure beingconcentrated in the outer walls of the building,the structure contributed significantly to, andindeed determined, the visual expression ofthe architecture. Hal Iyengar, chief structuralengineer in the Chicago office of Skidmore,Owings and Merrill described the relationshipthus:

‘... the characteristics of the project createa unique structure and then the architectcapitalises on it. That’s exactly whathappened in the Hancock building.’20

A development of the cantilever tube idea isthe so-called ‘bundled-tube’ – a system inwhich the shear connection between thewindward and leeward walls is made byinternal walls as well as those on the sides ofthe building. This results in a square gridarrangement of closely spaced ‘walls’ ofcolumns. The Sears Tower in Chicago, also bySkidmore, Owings and Merrill (Fig. 7.22), hasthis type of structure which is expressedarchitecturally, in this case by varying theheights of each of the compartments createdby the structural grid. The structural system istherefore a significant contributor to theexternal appearance of this building.

Thus, among very high buildings someexamples of structure as architecture may befound. These are truly high tech in the sensethat, because the limits of technicalpossibility have been approached, structuralconsiderations have been given a high priority

in the design – to the extent that theappearance of the building has beensignificantly affected by them.

7.2.3.4 The lightweight buildingThe situation in which saving in weight is anessential requirement is another scenariowhich causes technical considerations to beallocated a very high priority in the design of abuilding. This often comes about when thebuilding is required to be portable. Thebackpacker’s tent – an extreme example of theneed to minimise weight in a portablebuilding – has already been mentioned.Portability requires not only that the buildingbe light but also that it be demountable –another purely technical consideration. Insuch a case the resulting building form isdetermined almost entirely by technicalcriteria.

As has been repeatedly emphasised, themost efficient type of structure is the form-active one and the traditional solution to theproblem of portable buildings is, of course,the tent, which is a tensile form-activestructure. The tent also has the advantage ofbeing easy to demount and collapse into asmall volume, which compressive form-activestructures have not, due to the rigidity whichthey must possess in order to resistcompression. This solution has thereforebeen widely used for temporary or portablebuildings throughout history and is found in avery wide range of situations from theportable houses of nomadic peoples to thetemporary buildings of industrialisedsocieties, whether in the form of tents forrecreation or temporary buildings for otherpurposes. Figure 7.23 shows an example ofstate-of-the-art engineering used for abuilding to house a temporary exhibition –another example of truly high-techarchitecture.

Although the field of temporary buildingsremains dominated by the tent in all its forms,the compressive form-active structure has alsobeen used for such purposes. A late-twentieth-century example was the building designed byRenzo Piano for the travelling exhibition of 95


20 Conversation with Janice Tuchman reported inThornton, C., Tomasetti, R., Tuchman, J. and Joseph, L.,Exposed Structure in Building Design, McGraw-Hill, NewYork, 1993.

IBM Europe (Fig. 7.24). This consisted of asemi-form-active vault which was ‘improved’ bytriangulation. The sub-elements werelaminated beechwood struts and ties linked bypolycarbonate pyramids. These elements werebolted together using aluminium connectors.The structure combined lightness of weight,which was achieved through the use of low-density materials and an efficient structuralgeometry, with ease of assembly – the twoessential requirements of a portable building.No technical compromises were made forvisual or stylistic reasons.

7.2.3.5 Special requirementsOther forms of special requirement besides theneed for a lightweight structure can result instructural issues being accorded the highest


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Fig. 7.23 Tent structure for temporary exhibition building, Hyde Park, London, UK; Ove Arup & Partners, structuralengineers. Lightweight, portable buildings may be considered as examples of genuine ‘high-tech’ architecture in any agebecause the forms adopted are determined almost entirely from structural and constructional considerations.

Fig. 7.24 Building for IBM Europe travelling exhibition;Renzo Piano, architect/engineer; Ove Arup & Partners,structural engineers. This building consists of a semi-form-active compressive vault. The ‘improved’ cross-section ofthe membrane is achieved with a highly sophisticatedcombination of laminated timber and plastic – each is amaterial which offers high strength for its weight. Technicalconsiderations reign supreme here to produce a portable,lightweight building.

priority in the design of a building to the pointat which they exert a dominating influence onits form. A classic example of this from thenineteenth century was the Crystal Palace inLondon (Fig. 7.25) which was built to housethe Great Exhibition of 1851.

The problem which Joseph Paxton, thedesigner of the Crystal Palace, was required tosolve was that of producing a building whichcould be manufactured and erected veryquickly (nine months elapsed between theoriginal sketch design and the completion ofthe building) and which could subsequentlybe dismantled and re-erected elsewhere.Given the immense size of the building,comparable with that of a Gothic cathedral,the technical problem was indeed formidable.Paxton’s solution was to build a glasshouse –a glass envelope supported by an exposedstructure of iron and timber. It is difficult to

imagine any other contemporary structuralsolution which could have met the designrequirements. Possibly a series of very largetents would have sufficed – there was inexistence at the time a fairly large canvas- andrope-making capability associated withshipbuilding and a tradition of large tentmanufacture. Tents would not, however, haveprovided the lofty interior which was desirableto display adequately the latest products ofindustry. The Crystal Palace not only solvedthe problem of the large and lofty enclosure; itwas itself a demonstration of the capabilitiesof the latest industrial processes andtechniques of mass production.

The technology used for the building wasdeveloped by the builders of glasshouses forhorticulture, of whom Paxton was perhaps themost innovative. It contained much that theenthusiast of structural engineering and 97


Fig. 7.25 Crystal Palace, London, UK, 1851; Joseph Paxton, architect/engineer. The Crystal Palace was a truly high-techbuilding and an inspiration to generations of modern architects. Unlike many twentieth-century buildings to which thelabel High Tech has been applied, it was at the forefront of what was technically possible at the time. The major decisionsaffecting the form of the building were taken for technical reasons and were not compromised for visual or stylistic effect.The building has technical shortcomings, such as the poor durability of the many joints in the external skin, but in thecontext of a temporary building it was appropriate that these were given a low priority.

industrial technology could enjoy. The post-and-beam structure was appropriate for thespans and loads involved. Form-active archeswere used as the horizontal elements in thepost-and-beam format to span the largecentral ‘nave’ and ‘transepts’, and non-form-active, straight girders with triangulated‘improved’ profiles formed the shorter spans ofthe flanking ‘aisles’. The glazing conformed toa ridge-and-furrow arrangement, which wasdesigned originally in connection withhorticultural glasshouses to improve thedaylight-penetration characteristics – itprovided some shade during the hours aroundmid-day when the sun was high in the sky butadmitted more light in the early morning andlate evening. Although this characteristic wasnot particularly important in the case of theCrystal Palace, the arrangement enhanced thestructural performance by giving the glasscladding a structurally ‘improved’, corrugatedcross-section. Many other examples of goodtechnology were features of the building – oneof which was that the secondary beamssupporting the glazing served also as rainwaterguttering to conduct the run-off to the columnswhose circular hollow cross-sections, as wellas having ideal structural shapes forcompression elements, allowed them to

function as drain pipes. Another example wasthat much of the structure was discontinuousand this, through the elimination of the ‘lack-of-fit’ problem (see Appendix 3), together withthe very large degree of component repetition,facilitated both the rapid manufacture of theelements by mass-production techniques andthe very fast assembly of the building on site.

The building was therefore at the forefrontof contemporary technology – a genuineexample of a high-tech building – and wasideally suited to its purpose, which was tohouse a temporary exhibition. The technicalshortcomings of the arrangement – the lack ofthermal insulation, the susceptibility to leaksat the many joints in the cladding and thequestionable long-term durability of thestructure and of the cladding joints – were notsignificant in this context, as they would havebeen in a permanent building.

Many twentieth-century Modern architectshave been inspired by the glass-clad frameworkof the Crystal Palace. As was the case with thelater examples of ‘technology transfer’ alreadymentioned, although with some notableexceptions such as the Patera Buildingdescribed below, it was the imagery ratherthan the technical reality which was attractiveto them.


Fig. 7.26 Patera Building;Michael Hopkins, architect;Anthony Hunt Associates,structural engineers. Thebuilding consists of alightweight steel frameworkwhich supports an insulatedcladding system and fullyglazed end walls. Theprincipal structuralelements are external andthe purlins and claddingrails are located within thecladding zone to give a veryclean interior. (Photo:Anthony Hunt Associates)

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The Patera Building, by Michael Hopkinswith Tony Hunt as structural engineer (Fig7.26) has been directly compared to theCrystal Palace because its design was alsobased on the principle of pre-fabrication. Theproject was an attempt to address theproblem of the poor architectural quality ofmost industrial estates by producing abuilding system which would be economic,flexible and stylish and linking this to adevelopment company which would act as theco-ordinator of industrial estates. Thedevelopment company would acquire land,design a layout of building plots and installinfrastructure. Individual tenant clients wouldthen have buildings tailor-made to theirrequirements within a consistent style offeredby a building system. The buildings would, ineffect, be industrial apartments capable ofbeing adapted to different client requirementsand offered for rent for varying lengths oftenure to suit clients’ needs.

The principal hardware element in theconcept was a basic building shell which couldbe erected and fitted out quickly to meet theneeds of an individual tenant and then easilyadapted to suit the requirements ofsubsequent tenants. It was envisaged that thescale of the operation would allow thebuilding to be treated as an industrialproduct; it would be developed and tested inprototype form and subsequentlymanufactured in sufficient numbers to coverits development costs.

It was envisaged that the erection of thebuilding would occur in three phases. The first ofthese was the laying of a rectangular foundationand ground-floor slab in which services would beincorporated. This was the interface between thesuperstructure and the site and rendered thebuilding non-site-specific. The building could bebuilt anywhere that this standard rectangularslab could be laid. The second stage was theerection of the superstructure, a shell ofcladding, incorporating trunking for electricaland telephone services, supported on a steelframework. The third stage was the subdivisionand fitting out of the interior to meet specificclient requirements.

The structure of the building consisted of aseries of triangulated portal frameworks whichspanned 13.2 m across the building, linked byrectangular-hollow-section purlins andcladding rails spaced 1.2 m apart and spanning3.6 m between the main frames. The mainframeworks were ingeniously designed to meetexacting performance requirements whichcalled for a structure that would be of stylishappearance with, for ease of containerisation,no element longer than 6.75 m and, for ease ofconstruction, no element heavier than couldbe lifted by a fork-lift truck (Fig. 7.27). To meet 99


Fig. 7.27 Patera Building; Michael Hopkins, architect;Anthony Hunt Associates, structural engineers. Technicalconsiderations, such as the need for containerisation andfor simple assembly with a fork-lift truck exerted a majorinfluence on the design. (Photo: Anthony Hunt Associates)

these requirements a hybrid 2-hinge/3-hingeportal framework was chosen. The inherentefficiency of the semi-form-active arrangement,together with the full triangulation of theelements and the relatively small ratio of spanto depth that was adopted, allowed very

slender circular-hollow-section sub-elementsto be used. Each portal consisted of twohorizontal and two vertical sub-units whichwere pre-fabricated by welding. Cast-steeljointing components allowed the use of veryprecise pin-type site connections and these


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Fig. 7.28 PateraBuilding; MichaelHopkins, architect;Anthony HuntAssociates, structuralengineers. The ingenioususe of pin connectionsand cast nodes allowed afully rigid joint to bemade between theprincipal elements whichcould be easilyassembled. (Photo:Anthony HuntAssociates)

Fig. 7.29 PateraBuilding. The mid-spanjoint in the primarystructure has a three-hinge tension-only link.Under gravitational loadthe latter collapses andthe joint as a wholebehaves as a hinge.Under wind uplift thetension-only link comesinto play and theconnection becomesrigid. The devicemaintains the laterally-restrained lower boomsof the structure incompression under allconditions of load.(Photo: Anthony HuntAssociates)

were cleverly arranged at the junction betweenthe horizontal and vertical elements to providea rigid connection there (Fig. 7.28).

The hybrid 2-hinge/3-hinge arrangementwas adopted to eliminate the need foradditional lateral bracing of the compressionside of the structure by ensuring that theinner booms of the main elements, whichwere restrained laterally by the cladding,remained in compression under all conditionsof loading. The key to this behaviour was aningenious 3-pin tension-only link between thetop elements of the portal at the central joint(Fig. 7.29). Under gravitational load, this wassubjected to compression and collapsed toproduce a hinge joint between the mainelements at the mid-span position whichensured that compression was concentratedin the inner booms of the frame. If loadreversal occurred due to wind uplift, reversalof stress within the structure did not occurbecause the tension-only link now becamepart of the structure and converted the mainframe to a 2-hinge arrangement due to themid-span joint between the horizontalelements becoming rigid. This meant that thelaterally-restrained inner boom remained incompression and that most of the outer boomcontinued to be subjected only to tension.The need for lateral restraint for the outerbooms was therefore eliminated under allconditions of load.

The Patera building is therefore an exampleof architecture resulting from a skilful technicalsolution to a set of very particularrequirements. In this respect it is similar to theCrystal Palace.

7.2.3.6 ConclusionIn most of the cases described in this sectionthe buildings have consisted of little otherthan a structure, the form of which wasdetermined by purely technical criteria. Theinherent architectural delight thereforeconsisted of an appreciation of ‘pure’ structuralform. These truly high-tech structure types,especially the long-span, form-activestructures, are considered by many to bebeautiful, highly satisfying built forms.

Billington21 goes so far as to argue that theymay be considered to be examples of an artform and this issue has been discussed morerecently by Holgate22. It is questionable,however, although it may not be important,whether a shape which has been evolved frompurely technical considerations can beconsidered to be a work of art, howeverbeautiful it may appear to those with thetechnical knowledge to appreciate it.

7.2.4 Structure as form generator/structureacceptedThe terms structure as form generator and structureaccepted are used here to describe a relationshipbetween structure and architecture in whichstructural requirements are allowed toinfluence strongly the forms of buildings eventhough the structure itself is not necessarilyexposed. In this type of relationship theconfiguration of elements which is mostsensible structurally is accepted and thearchitecture accommodated to it. The reasonwhy two cases are distinguished is that thecloseness of the link between the architecturaland the structural agendas is subject toconsiderable variation. Sometimes it is verypositive, with the form-generating possibilitiesof structure being used to contribute to anarchitectural style. Alternatively, even thoughthe overall form of a building may have beendetermined largely to satisfy structuralrequirements, the architectural interest may lieelsewhere.

The vaulted structures of Roman antiquityare an example of the first of thesepossibilities. The large interior spaces of thebasilicas and bath houses of Imperial Rome,which are one of the chief glories of thearchitecture of the period and which areamong the largest interiors in Westernarchitecture, were roofed by vaults and domes

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21 Billington, D. P., Robert Maillart, MIT Press, Cambridge,MA, 1989.

22 See Holgate, A., The Art in Structural Design, ClarendonPress, Oxford, 1986 and Holgate, A., Aesthetics of BuiltForm, Oxford University Press, Oxford, 1992.


Fig. 7.30 ThePantheon, Rome,2nd century AD.The hemisphericalconcrete dome issupported on acylindrical drumalso of concrete.Both have thickcross-sectionswhich have been‘improved’ by theuse of coffers orvoids of varioustypes and thesetechnical deviceshave beenincorporated intothe visual schemeof the interior.

Fig. 7.31 The Basilica ofConstantine, Rome, 4thcentury AD. The vaultedroof of the principalinternal volume issupported on very thickwalls from which largevoids with vaulted ceilingshave been extracted toreduce the volume ofstructural materialrequired. These have beenused to create variety inthe disposition of internalvolumes. As at thePantheon the technical andvisual programmes of thearchitecture have beenbrilliantly combined.

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of masonry or unreinforced concrete (Figs 7.30to 7.32). The absence at the period of a strongstructural material which could withstandtension dictated that compressive form-activestructures be adopted to achieve the largespans involved. Lofty interiors of impressivegrandeur were created by placing the vaultsand domes on top of high walls which weregiven great thickness so as to accommodatethe lateral thrusts produced at the wall-heads.

The Roman architects and engineers quicklyappreciated that the walls did not have to besolid and a system of voided walls was developedwhich allowed a large overall thickness to beachieved using a minimum volume of material.The coffering on the undersides of vaults anddomes was a similar device for reducing thevolume and therefore weight of material involved.The walls of the main spaces in these vaultedstructures are semi-form-active elements with‘improved’ cross-sections. They carry axial loaddue to the weights of the vaults which theysupport and bending moments caused by thelateral thrusts of the vaults.

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Fig. 7.32 Construction system of Roman vault. Thelargest interiors in Rome were constructed in unreinforcedconcrete which was placed in a thin skin of brickworkwhich acted as permanent formwork. The structuralarmature was then faced in marble to create a sumptuousinterior. Although structural requirements dictated theoverall form of the building, no part of the structure wasvisible.

(a)

(b)

Both the voiding of the walls and thecoffering of the vaults were used by thearchitects of Imperial Rome to create adistinctive architecture of the interior. ThePantheon in Rome (Fig. 7.30) is one of thebest examples. In this building the pattern ofthe coffering on the underside of the domehelps to increase the apparent size of theinterior and the voids and recesses in thewalls of the drum which supports the domecreate an illusion of the walls dissolving sothat the dome appears to float above theground.

Such techniques were further developed inthe designs for bath houses and basilicas(Fig. 7.31). Interiors were created in whichthe possibilities offered by the structuralsystem were fully exploited to producespaces of great interest and variety. Thedevice of the transverse groined vault wasalso used in these buildings – againprincipally for a technical, though notstructural, reason. This was adopted in orderto create flat areas of wall at high level whichcould be pierced by clerestory windowsadmitting light into what would otherwisehave been dark interiors.

The vaulted structures of Imperial Romeare therefore buildings in which featureswhich were necessary for structural reasonswere incorporated into the aestheticprogramme of the architecture. This was notcelebration of technology but rather theimaginative exploitation of technicalnecessity.

Many twentieth-century architectsattempted to produce a modern architecture inwhich the same principles were followed. Oneof the most enthusiastic exponents of theacceptance of structure as a generator of formwas Le Corbusier, and the structuraltechnology which he favoured was that of thenon-form-active reinforced concrete flat slab,capable of spanning simultaneously in twodirections and of cantilevering beyondperimeter columns. The structural action waswell expressed in his famous drawing (Fig.7.33) and the architectural opportunities whichit made possible were summarised by Le

Corbusier in his ‘five points of a newarchitecture’23.

This approach was used by Le Corbusier inthe design of most of his buildings. Thearchetype is perhaps the Villa Savoye (Fig.7.34), a building of prime importance in thedevelopment of the visual vocabulary oftwentieth-century Modernism. As in Romanantiquity, the structure here is not so muchcelebrated as accepted and its associatedopportunities exploited. Later buildings by LeCorbusier, such as the Unité d’Habitation atMarseilles or the monastery of La Tourettenear Lyon, show a similar combination ofstructural and aesthetic programmes.

The ‘Modernistic’ (as opposed to Modern –see Huxtable24) skyscrapers which wereconstructed in the 1920s and 1930s in the USA,such as the Chrysler (Fig. 7.35) and EmpireState buildings, are further examples of theadoption but not expression of a newstructural technology – in this case that of themulti-storey steel frame. Although thearchitectural treatment of these buildings was


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23 Le Corbusier, Five Points Towards a New Architecture, Paris,1926.

24 Huxtable, A. L., The Tall Building Reconsidered: The Search fora Skyscraper Style, Pantheon Books, New York, 1984.

Fig. 7.33 The advantages of the structural continuityafforded by reinforced concrete are admirably summarisedin the structural armature of Le Corbusier’s Domino Houseof 1914. Thin two-way spanning slabs are supporteddirectly on a grid of columns. The stairs provide bracing inthe two principal directions.

more conventional than those by Le Corbusier,making use of a pre-existing architecturalvocabulary, they were nevertheless novel formswhich owed their originality to the structuraltechnology upon which they depended.

Another example of an early-twentieth-century building in which an innovativestructure was employed, although notexpressed in an overt way, was the Highpoint 1building in London by Berthold Lubetkin andOve Arup (Fig. 7.36). Here the structure was a‘continuous’, post-and-beam arrangement ofreinforced concrete walls and slabs. There wereno beams and few columns and therein lay oneof its innovatory aspects. The system offeredgreat planning freedom: where openings wererequired, the walls above acted as beams. Thelevel of structural efficiency was modest butwas entirely appropriate for the spansinvolved, and other aspects of the structure,such as its durability, were also highlysatisfactory. The method of construction wasalso original. The structure was cast on site ona reusable, moveable system of woodenformwork – also designed by Arup – and thebuilding represented, therefore, an harmoniousfusion of new architectural ideas withstructural and constructional innovations. Thearchitectural language used was discreet,however, and made no grand statement ofthese innovative technical features.


Fig. 7.35 ChryslerBuilding, New York,USA, 1930; William VanAllen, architect.Although the overallforms of Modernisticskyscrapers such as theChrysler Building aredetermined by the steelframe structure thevisual treatment is not.(Photo: Petra Hodgson)

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Fig. 7.34 Villa Savoye,Poissy, France, 1931;architect, Le Corbusier.The reinforced concretestructural armature ofthis building has, to alarge extent, determinedits overall form. Manyother factors connectedto Le Corbusier’s searchfor a visual vocabularyappropriate to the‘machine age’contributed to the finalappearance of thebuilding, however.(Photo: Andrew Gilmour)


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Fig. 7.36 Highpoint 1, London, UK, 1938; Berthold Lubetkin, architect; Ove Arup, structural engineer. The structure ofthis building is of reinforced concrete which lends itself to a rectilinear form. The visual treatment was as muchinfluenced by stylistic ideas of what was visually appropriate for a modern architecture as it was by technical factorsconnected with the structure. (Photo: A. F. Kersting)

(a) (b)

Fig. 7.37 Willis, Faber and Dumas Office, Ipswich, UK, 1974; Foster Associates, architects; Anthony Hunt Associates,structural engineers. This building may be considered to be a late Modern equivalent of the Villa Savoye (Fig. 7.34).The relationship between structure, space planning and visual treatment is similar in both buildings. (Photo: JohnDonat)

A late-twentieth-century example of thepositive acceptance rather than the expressionof structural technology is found in the Willis,Faber and Dumas building in Ipswich, UK byFoster Associates (Fig. 7.37) with the structuralengineer Tony Hunt. The structure is of thesame basic type as that in Le Corbusier’sdrawing (Fig. 7.33) and its capabilities werefully exploited in the creation of the curvilinearplan, the provision of large wall-free spaces inthe interior and the cantilevering of the floorslabs beyond the perimeter columns. Thebuilding has a roof garden and free non-structural treatment of both elevation and planand it therefore conforms to the requirementsof Le Corbusier’s ‘five points’.

Another example by Foster and Hunt is thepilot head office for IBM UK at Cosham (Fig.7.38). This was intended to serve as atemporary UK main office for the IBM companyand was located on a site adjacent to one onwhich a permanent headquarters building forIBM UK was already under construction. Whenthe design was commissioned, IBM, incommon with many rapidly-expanding

companies at the time, was making significantuse of clusters of timber-framed portablebuildings and envisaged that this type ofaccommodation would be the most suitablefor the temporary head office. FosterAssociates were instructed to report on themost suitable of the proprietary systems thenavailable and to advise on the disposition ofthe buildings on the site. This possibility wasindeed considered, but the solution whichFoster recommended was that of a custom-designed building based on lightweightindustrialised components, and it was thisscheme that was finally executed.

Due to the need to compete with theportable building alternative on cost andspeed of erection, and due to the fact that theground conditions were poor because the sitewas a former land-fill rubbish tip, technicalconsiderations exerted a major influence onthe design. The design of the structure wasparticularly crucial to the success of theproject. Tony Hunt considered using long piles(40 ft) to reach firm strata, but this would havemeant reducing the number of separate


Fig. 7.38 IBM pilothead office, Cosham,UK, 1973; FosterAssociates, architects;Anthony HuntAssociates, structuralengineers. Intended astemporaryaccommodation, Fosterand Hunt provided astylish building for thesame cost and withinthe same time-scale asthose of a cluster oftemporary buildings,which is what the clientoriginally envisaged.The form adopted wasto a large extentdictated by structuralrequirements. (Photo:Anthony HuntAssociates)

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foundations to a minimum and the resultinglong-span structure would have been slow toerect and expensive to produce. The alternativewas to use a short-span structure inconjunction with a rigid raft foundation thatwould ‘float’ on the low-bearing-capacitysubstrata. A number of such systems wereconsidered. The favoured system wasconfigured with lightweight triangulatedgirders which created a combined structureand services zone at roof level which wascrucial to the provision of the requiredflexibility in the use of space (Fig. 7.39).

The IBM pilot head office was remarkablysuccessful in almost every respect. It providedthe client with a distinctive, stylish buildingwhich was enjoyable in use for all grades ofemployee, and which was undoubtedly apreferable solution to the client’s requirementsthan the assemblage of proprietary portablebuildings that they had originally envisaged. Ameasure of the success of the building wasthat, although it had been intended astemporary accommodation to last for a periodof three to four years, it was retained by thecompany, following the completion of the

permanent head office, and converted for useas an independent research unit.

The choice of the lightweight steelworksystem was crucial to the success of the IBMbuilding. It was a straightforward assemblageof proprietary Metsec components. This wasboth inexpensive and allowed the structure tobe rapidly erected on site using no plant largerthan a fork-lift truck. The resulting speed andeconomy was what made the buildingcompetitive with the alternatives. The structuredoes not form a significant visual element asmost of it is concealed behind finishingelements. It did, however, exert a majorinfluence on the final form of the building. Thisis therefore structure as form generator rather thanstructure as architecture.

The architectural interest in the IBMbuilding lies in the stylish way in which thevarious components, particularly the finishingcomponents such as the glass external wall,were detailed. Thus, although the need toproduce a light and economical structurewhich could be erected very quickly played asignificant role in determining the overall formof the building, the relationship between


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Fig. 7.39 IBM pilothead office, Cosham,UK, 1973; FosterAssociates, architects;Anthony HuntAssociates, structuralengineers. The structurewas a steel frameworkwith lightweighttriangulated beamelements. These createda combined structuraland services zone, atroof level which wasessential to achieve therequired flexibility inthe use of the interior.(Photo: Anthony HuntAssociates)

structure and architecture is here much lessdeterministic than was the case with thevaulted buildings of Roman antiquity or theWillis, Faber and Dumas building, where thefinal form was expressive of the behaviour ofthe constituent structural materials.

In the IBM pilot head office building, therelationship between structure andarchitecture is less direct than in the otherbuildings described in this section and isperhaps significantly different to warrant adifferent terminology, namely structure accepted.In this kind of relationship, a form is adoptedwhich is sensible structurally but thearchitectural interest is not closely related tostructural function. This is a relationshipbetween structure and architecture which iscommonly found in contemporary architectureand innumerable other examples could becited. It has, in fact, been the dominantrelationship between structure andarchitecture since the time of the ItalianRenaissance (see Section 7.3).

7.2.5 Structure ignored in the form-makingprocess and not forming part of theaesthetic programmeSince the development of the structuraltechnologies of steel and reinforced concrete ithas been possible to design buildings, at leastto a preliminary stage of the process, withoutconsidering how they will be supported orconstructed. This is possible because thestrength properties of steel and reinforcedconcrete are such that practically any form canbe built, provided that it is not too large andthat finance is not a limiting consideration.This freedom represents a significant and oftenunacknowledged contribution which structuraltechnology has made to architecture, liberatingarchitects from the constraints imposed by theneed to support buildings with masonry andtimber.

For most of the period following theintroduction of steel and reinforced concreteinto building in the late nineteenth century, thedominant architecture in the industrialisedworld was that of International Modernism. Mostof the architects of this movement subscribed to

the doctrine of rationalism and held the viewthat buildings should be tectonic, i.e. theybelieved that the visual vocabulary shouldemerge from, or at least be directly related to,the structural armature of the building, whichshould be determined by rational means. Theconsequence of this was that the forms of mostbuildings were relatively straightforward from astructural point of view – based on the geometryof the post-and-beam framework.

An additional factor which favoured the useof simple forms was that the design andconstruction of very complex forms waslaborious and costly, thus inhibiting the fullexploitation of the potential offered by thesenew materials. There were of courseexceptions. Erich Mendelsohn’s Einstein Towerin Potsdam (see Fig. iii), Gerrit Rietveld’sSchroeder House in Utrecht and Le Corbusier’schapel at Ronchamp (Fig. 7.40) weresuccessfully realised despite having complexforms unrelated to structural function. Theirrelatively small scale meant that it was notdifficult in each case to produce a structuralarmature which would support the form, ratherin the manner of the armature of a sculpture.

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Fig. 7.40 Notre-Dame-du-Haut, Ronchamp, France, 1954;Le Corbusier, architect. Structural considerations haveplayed very little part in the determination of the form ofthis building. Its small scale together with the excellentstructural properties of reinforced concrete, which wasused for the roof, meant that it could be constructedwithout difficulty. (Photo: P. Macdonald)

The introduction of the computer in the latetwentieth century, firstly as a tool for structuralanalysis and subsequently as a design aid,which allowed very complex forms to bedescribed and cutting and fabricatingprocesses to be controlled, gave architectsalmost unlimited freedom in the matter ofform. This was a major factor in theintroduction of the very complex geometrieswhich appeared in architecture towards theend of the twentieth century. A good example isFrank Gehry’s highly complex and spectacularGuggenheim Museum in Bilbao, Spain.

Wolf Prix, of Coop Himmelblau, was anotherlate-twentieth-century architects who fullyexploited this freedom:

‘... we want to keep the design momentfree of all material constraints ...’25

‘In the initial stages structural planning isnever an immediate priority ...’26

Great ingenuity was often required of theengineers who devised the structural solutionsfor buildings whose forms had been devised ina purely sculptural way. That of the chapel atRonchamp is remarkable due to the greatsimplicity of the structure which supports thefree-form roof. The walls of the building are ofself-supporting stone masonry rendered white.There is a gap between the tops of these andthe underside of the roof so as to admit asmall amount of light into the interior in agesture which is architecturally significant. Thewalls do not therefore carry the weight of theroof.

The upwardly curving, oversailing roof isformed by a thin shell of reinforced concretewhich conceals an integral and conventionalpost-and-beam reinforced concrete framework.Reinforced concrete columns of small cross-section are embedded in the masonry walls ina regular grid, and carry beams which span

across the building. These provide supportfrom above for the roof shell, which sweeps upat the edges of the building to conceal them.Thus, although the overall form of the buildingbears no relation to the manner in which itfunctions structurally, a satisfactory andrelatively simple structure was accommodatedwithin it.

In more recent times a similar approach tothat adopted by Le Corbusier at Ronchamp, atleast so far as the relationship of structure toarchitecture is concerned, is to be found in theworks of the architects of the Deconstructionschool. The structural organisation of buildingssuch as the rooftop office in Vienna by CoopHimmelblau (see Fig. 1.11) or the Vitra DesignMuseum in Basel by Frank Gehry (Fig. 7.41)were relatively straightforward. The same maybe said of Daniel Libeskind’s Jewish Museumin Berlin (Fig. 7.42). More complexarrangements were required to realise thecomplicated geometries of Libeskind’sextension to the Victoria and Albert Museumin London (Figs 7.43 and 7.44) and the newImperial War Museum in Manchester.

Two important considerations must betaken into account when form is devisedwithout recourse to structural requirements.Firstly, because the form will almost certainlybe non-form-active, bending-type internal forcewill have to be resisted. Secondly, themagnitudes of the internal forces which aregenerated are likely to be high in relation tothe load carried. The implications of both ofthese considerations are that structuralmaterial will be inefficiently used and that theelement sizes required to produce adequatestrength will be high. This is a scenario whichcan result in structures which are clumsy andungainly.

A scale effect also operates because thestrength of structural material remainsconstant even though the size of the structureincreases. As was discussed in Chapter 6, allstructural forms, whatever their shape, tend tobecome less efficient as spans increase. Themaximum span for a given form occurs whenthe strength of the material is fully occupied,supporting the self-weight of the structure. If


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25 Quotations from On the Edge, the contribution of WolfPrix of Coop Himmelblau to Noever, P. (Ed.), Architecturein Transition: Between Deconstruction and New Modernism,Prestel-Verlag, Munich, 1991.

26 Ibid.


Fig. 7.41 VitraDesign Museum,Basel, Switzerland,1989; Frank Gehry,architect. From atechnical point ofview forms such asthis present achallenge. Theirconstruction ismade possible bythe excellentstructural propertiesof present-daymaterials such asreinforced concreteand steel. The scaleof such a projectmust be smallhowever. (Photo: E.& F. Mclachlan)

Fig. 7.42 JewishMuseum, Berlin,1999; DanielLibeskindArchitekturburo,architects. The useof a reinforcedconcrete structuralframework hasallowed both ahighly sculpturedoverall form to becreated and a highdegree of freedom tobe achieved in thetreatment of thenon-structuralcladding of theexterior.

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Fig. 7.43 Design for an extension to the Victoria and Albert Museum, London, UK, 1995–; Daniel LibeskindArchitekturburo, architects; Ove Arup & Partners, structural engineers. Structural considerations had little influence onthe original design for this building.

Fig. 7.44 Design for an extension to the Victoria and Albert Museum, London, UK, 1995–; Daniel LibeskindArchitekturburo, architects; Ove Arup & Partners, structural engineers. The cross-section reveals that the structure is afairly conventional post-and-beam framework. The relatively small scale of the project, the excellent properties of modernstructural materials and the judicious use of structural continuity allowed this complex form to be realised.

the form adopted is fundamentally inefficient,because it has been designed withoutreference to structural requirements, themaximum possible span may be quite small.

The neglect of structural issues in thedetermination of the form of a building cantherefore be problematic if a large span isinvolved. The small scale of the buildingsalready mentioned meant that the internalforces were not so large that they could not beresisted without the use of excessively largecross-sections. Eero Saarinen’s terminal forTWA at Idlewild (now Kennedy) Airport, NewYork (Fig. 7.45) paid similar disregard tostructural logic. Although the roof of thisbuilding was a reinforced concrete shell it didnot have a form-active shape. The form wasdetermined from visual rather than fromstructural considerations and, because it waslarger than Ronchamp, difficulties occurredwith the structure. These were overcome bymodifying the original design to strengthen theshell in the locations of highest internal force.

Jorn Utzon’s Sydney Opera House isanother example of this type of building (Fig.7.46). In this case, the scale was such that itwas impossible to overcome theconsequences of the complete disregard ofstructural and constructional concerns in thedetermination of the form. In the resultingsaga, in which the form of the building had tobe radically altered for constructional reasons,the architect resigned and the client was facedwith a protracted construction period and withcosts which were an order of magnitudegreater than had originally been envisaged.Amid great political controversy, the buildingwas nevertheless completed and has becomea distinctive image which is synonymous withSydney, if not with Australia, rather as theEiffel Tower, Big Ben or the Statue of Libertyhave come to represent other famous citiesand their respective countries. Although theexpertise of Ove Arup and Partners in solvingthe structural and constructional problemsbrought about by Utzon’s inspired, iftechnically flawed, original design areundisputed, the question of whether the finalform of the Sydney Opera House is good

architecture remains open. This building mayserve as a warning to architects who choose todisregard the inconveniences of structuralrequirements when determining form. The 113


Fig. 7.45 TWA Terminal, Idlewild (now Kennedy) Airport,New York, USA, 1962; Eero Saarinen, architect; Ammanand Whitney, structural engineers. The form here was farfrom ideal structurally and strengthening ribs of greatthickness were required at locations of high internal force.The structure was therefore inefficient but constructionwas possible due to the relatively modest spans involved.(Photo: R. J. Mainstone)

Fig. 7.46 Opera House, Sydney, Australia, 1957–65; JornUtzon, architect; Ove Arup & Partners, structural engineers.The upper drawing here shows the original competition-winning proposal for the building which proved impossibleto build. The final scheme, though technically ingenious, isconsidered by many to be much less satisfactory visually.The significant difference between this and the buildings inFigs 7.41 to 7.45 is one of scale.

consequence may be that the final form willbe different from their original vision in wayswhich they may be unable to control. Theignoring of structural logic in the creation ofform is indeed possible but only in thecontext of short spans. The success of therecent buildings by Coop Himmelblau, Gehryand Libeskind has depended on thissituation.

In all of the buildings considered in thissection the structure is present in order to doits mundane job of supporting the buildingenvelope. In this kind of architecture structuralengineers act as facilitators – the people whomake the building stand up. It should not bethought, however, that the world of structureshas played no part in the evolution of the free-form architecture which became fashionable inthe late twentieth century. It was the structuraltechniques which were developed in thetwentieth century which made such anarchitecture possible, and which gavearchitects the freedom to exploit geometrieswhich in previous centuries would have beenimpossible to realise.

7.2.6 ConclusionThis section has reviewed the interactionbetween structure and architecture and hasshown that this can operate in a variety ofways. It is hoped that the several categorieswhich have been identified for thisrelationship, however artificial they may be,nevertheless contribute to the understandingof the processes and interactions whichconstitute architectural design.

Six broad categories were identified andthese may be considered to be grouped indifferent ways – something which shedsfurther light on the design process. Onegrouping would be to subdivide the varioustypes of relationship into two broadcategories – structure exposed and structure hiddenfrom view. There are three sub-categories of thestructure exposed relationship: ornamentation ofstructure, structure as ornament and structure asarchitecture. Structure hidden also contains twosub-categories: structure as form generator/structure accepted and structure ignored.

The original six categories may alternativelybe considered as grouped into two otheroverarching categories namely structure respected,in which forms are adopted which perform wellwhen judged by technical criteria, and structuredisrespected, in which little account is taken ofstructural requirements when the form isdetermined. The first of these would includeornamentation of structure, structure as architecture,structure as form generator and structure accepted.The second would include structure as ornamentand structure ignored.

This second way of regarding the variouspossible relationships between structure andarchitecture focuses attention on the types ofcollaboration which can exist betweenarchitects and engineers, a fascinating aspectof the history of architecture. If structure is tobe respected, engineers and architects mustcollaborate in a positive way over the design ofa building. The engineer is then a member ofthe team of designers which evolves the formof the building. Where the relationships fallinto the category of structure disrespected theengineer can be simply a technician – theperson who works out how to build a formwhich has been determined by someone else.

7.3 The relationship betweenarchitects and engineers

Collaboration has always been requiredbetween architects and those who have thetechnical expertise to realise buildings. Thenature of the relationship has taken manyforms, and the form in play at any time hasalways influenced the nature of the interfacebetween structure and architecture.

In Greek and Roman antiquity, therelationship between the equivalents ofarchitects and engineers must have been veryclose in order to achieve the creation ofbuildings in which the requirements ofstructure and architecture were reconciled in avery positive way. In this period the architectand engineer would, in many cases, have beenthe same individual – the master builder. This


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methodology brought into being some of thegreatest buildings of the European Classicaltradition, always in the context of structurerespected. Ornamentation of structure produced theGreek temples (Fig. 7.1) and the Romantriumphal arches. Structure as form generator wasthe relationship that existed in the creation ofthe great interiors of Imperial Rome such asthe Pantheon (Fig. 7.30) and the Basilica ofConstantine (Fig. 7.31). In each case therelationship between structure andarchitecture was positive; the architecture wasborn out of a need to satisfy structuralrequirements. It meant that those responsiblefor the technical make-up of buildings also

played a significant role in determining theirarchitectural qualities and interest.

This type of relationship between theequivalents of architects and engineers wasmaintained during the medieval period inwhich the Gothic buildings, which were aversion of ornamentation of structure, wereproduced but it almost disappeared at thetime of the Italian Renaissance.

Andrea Palladio, for example, who began hisworking life as a stone mason and who wasentirely confident in the technology at hisdisposal, designed buildings which werepractical and sensible from a structuralviewpoint (Fig. 7.47). They belonged in the 115


Fig. 7.47 Villa Emo,Fanzolo, Italy, 1564;Andrea Palladio,architect. Structuralrequirements exerted astrong influence on theform of this masonry andtimber building but thearchitectural interest layelsewhere.

(a)

(b)

category structure accepted rather than structure asform generator, however, because thearchitectural interest of his work lay in the ideaof the building as a microcosm and his use ofharmonic proportion, hierarchicalarrangements of space and innovative uses ofclassical forms of ornamentation. The meansby which the buildings were constructed wereof little relevance to this agenda.

In Western architecture most of thebuildings from the Italian Renaissance to theModern period fall into this category. It issignificant that throughout this period theprincipal structural materials were masonryand timber. These are problematic structurallyin various ways27 and forced architects to adopt

structural forms which were sensible from astructural point of view. The requirements ofstructure had therefore to be respected but, inthe majority of buildings, the architecturalinterest lay elsewhere. This meant thatstructural considerations fell out of anydiscussion of architecture.

Two aspects of post-medieval architecturecontributed to this. Firstly, a subtle changeoccurred in the nature of the relationshipbetween structure and architecture becausethe structural armatures of buildings wereincreasingly concealed behind forms ofornamentation which were not directly relatedto structural function. The villa illustrated inFig. 7.47 is an example by Palladio. His designfor the Palazzo Valmarana in Vicenza (Fig. 7.2)is another. The Corinthian Order pilasterswhich were incorporated into the façade of thisbuilding formed the thin outer skin of a solidwall. The wall was the structural element and


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27 See Macdonald, A. J., Structural Design for Architecture,Architectural Press, Oxford, 1997, Chapters 5 and 6 fora discussion of these issues.

Fig. 7.48 St Paul’s Cathedral, London, UK, 17th century; Sir Christopher Wren, architect. In treatment of both the domeand the exterior wall the structural arrangement is not reflected in the visual programme.

the pilasters had a symbolic rather than astructural role. The reduction of elements withstructural origins to components in a visualvocabulary, which was typical of thearchitecture of the period, caused thestructural and aesthetic agendas to drift apart.This in turn had a profound effect on the typeof relationship which developed betweenarchitects and those who were responsible forthe technical aspects of the design of abuilding.

The second change that occurred from theItalian Renaissance onwards was that mostbuildings were structurally unambitious. Atechnology of masonry walls and timber floor

and roof structures existed whose capabilitieswere well understood and which presentedlittle challenge to builders. There were obviousexceptions, Brunelleschi’s dome in Florencebeing an excellent example (Fig. 7.13), but inthe majority of buildings there was no sense ofexcitement in relation to the structural make-up. The forms adopted were sensible from astructural point of view, but there were nofurther structural ambitions. Even with largebuildings such as St Paul’s Cathedral inLondon (Figs 7.48 to 7.50) in which seriousstructural challenges had to be met, thestructure made no obvious contribution to thearchitecture. 117


Fig. 7.49 St Paul’s Cathedral, London, UK, 17th century;Sir Christopher Wren, architect. The cross-section of thebuilding reveals that the structural arrangement isconventional with a high central nave and flying buttressescarrying the side thrusts created by the masonry vault. Thestructural action is concealed behind the external wall, theupper half of which is a non-structural screen.

Fig. 7.50 St Paul’s Cathedral, London, UK, 17th century;Sir Christopher Wren, architect. The dome is in three parts.The innermost part is a self-supporting masonryhemisphere. The outer skin is mounted on a timberframework supported by a cone of structural brickwork.

For example, the stone external walls of thisbuilding form a wallpaper-like screen, wrappedaround the core of the building, which bearslittle relation to its structural make-up. Thecross-section of the building is similar to thatof a medieval Gothic church and consists of ahigh vaulted central nave flanked by loweraisles and with flying buttresses providinglateral support for the vault (Fig. 7.49). None ofthis is visible, or suggested, on the exterior.

The uncoupling of the structural from thevisual agenda at St Paul’s also occurred in thedesign of the dome, where Wren did notrequire that the interior and exterior profilesbear any relation to each other. The dome wasconstructed in three layers (Fig. 7.50). The partwhich is visible in the interior is a self-supporting structure – a semi-form-active

hemisphere in masonry. On the exterior, theprofile of the dome is completely disconnectedfrom the way in which it operates structurally.The structure is a cone of brickwork which isentirely hidden from view and which supportsdirectly the stone cupola at the apex of thedome. The external profile of the dome is alightweight skin supported on a timberformwork built out from the structural core. Thebrick cone conforms to the form-active shapefor the principal load which it carries – that ofthe weight of the cupola – but its shape bearsno relation to the form of the dome which isseen on either the interior or the exterior of thebuilding. The architecture of the exterior of St Paul’s, including that of the external wall andof the dome, is therefore unrelated visually tothe structure which supports it.


Fig. 7.51 Train shed, St Pancras Station, London, UK, 1865; W. H. Barlow and R. M. Ordish, engineers. The architecturalqualities of the large iron-and-glass interiors of the nineteenth century went largely unrecognised at the time.118

The distance between the architectural andstructural agendas was perhaps generally at itsgreatest towards the end of the nineteenthcentury and is exemplified by buildings such asSt Pancras Station in London (1865). Here, oneof the largest iron and glass vaults of thecentury, by W. H. Barlow and R. M. Ordish (Fig.7.51), a spectacular example of what could beachieved with the new technology of structuraliron, was concealed behind the bulk of GilbertScott’s Midland Hotel in the High Victorian

Gothic style (Fig. 7.52). The two parts of thebuilding were each fine examples of their type,but they inhabited different worlds. Thearchitectural qualities of the train shed wentunrecognised: it was considered as simply avulgar product of industry, necessary but notbeautiful, and the citizens of London wereprotected from the sight of it by a fine essay inRuskinian northern-Italian Gothic.

The visual disconnection of architecturefrom structure which is seen at St Paul’s

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Fig. 7.52 Midland Hotel,at St Pancras Station,London, UK, 1871; G.Gilbert Scott, architect. Theform of the train shed didnot influence thearchitectural agenda at StPancras.

Cathedral and St Pancras Station illustrateswell the approach which was adopted byWestern architects from the ItalianRenaissance onwards. Architects were stillinterested in structure, but only as a means ofrealising built form which was generated fromideas which were remote from technicalconsiderations. This approach to architecturewas made easier following the development ofthe structural technologies of steel andreinforced concrete in the late nineteenthcentury and it was used in much of the Modernarchitecture of the twentieth century. Steel andreinforced concrete had much better structuralproperties than timber or masonry andreleased architects from the need to payattention to structural requirements, at least incases where the limits of what was technicallyfeasible were not being approached. This madepossible, in the twentieth century, a new kindof relationship between structure andarchitecture – structure ignored.

A consequence of the distancing of theaesthetic from the technical agenda, themaking of a distinction between architectureand building, was that architects no longerevolved the forms of buildings in a trulycollaborative partnership with those who wereresponsible for the technical aspects of design.The latter became technicians, responsible forensuring that the technical performance of abuilding would be satisfactory but notcontributing creatively to its form orappearance.

Several of the prominent early Modernarchitects were, however, interested intectonics, the architectural expression of thefundamental elements of buildings that areresponsible for holding them up. This causedmore collaborative relationships betweenarchitects and engineers to develop. The statusquo was nevertheless maintained concerningthe relationships between architects andengineers, and the design of a building wasstill very much dominated by the architect asthe leader of the group of professionals whocollaborated over its production. Modernismespoused rationalism but carried with it muchof the baggage of nineteenth-century

Romanticism. One particularly strong aspect ofthis situation was the idea of the architect as aheroic figure – in the parlance of architecturalcriticism, the ‘Modern Master’. Thus, althougharchitecture became ever more dependentupon new structural technologies in thetwentieth century and therefore upon the skilland expertise of engineers, most architectscontinued to behave, as they had done sincethe Italian Renaissance, as the masters of thedesign process and to treat the other designersinvolved as mere technicians. This view wasendorsed by most of the critics and historiansof Modernism who paid little regard to thetechnology which underpinned the Modernaesthetic and gave scant acknowledgement tothe engineers who developed it. The names ofthe engineers of the classic buildings of earlyModernism by architects such as WalterGropius, Ludwig Mies van der Rohe and LeCorbusier are rarely mentioned.

The subservient position of engineers inrelation to the conceptual stages ofarchitectural design was maintained throughthe Modern period and has continued into thepresent day, where it may be observed to bestill operating in some of the most prestigiousarchitectural projects. The extremely complexforms devised by architects such as FrankGehry (Fig. 7.41), Zaha Hadid or DanielLibeskind (Figs 7.43 and 7.44), for example,provide serious challenges to engineers, butthe engineers are not involved in the initialdetermination of the form.

A new type of relationship betweenarchitects and engineers, in which very positivecollaborations occurred with engineersinfluencing the design of buildings from thevery earliest stages, did, however, develop inthe twentieth century. The catalyst which madethis possible was the re-introduction oftectonics into the architectural discourse. Thisdrew attention to the visual qualities of theemerging structural technologies of ferrousmetal and reinforced concrete. It resulted inthe re-examination, from an architectural pointof view, of much nineteenth-century buildingthat had escaped the notice of a contemporaryarchitectural culture which had been


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preoccupied with revivals and ‘battles ofstyles’. Buildings such as the Crystal Palaceand the long-span train sheds of the mid-nineteenth century were seen by some earlyModernists to have interesting architecturalqualities. Buildings created by twentieth-century equivalents of the railway engineerswere also considered to be worthy of attentionand were given space in the architecturalmedia. Thus, aircraft hangars (surely thetwentieth-century equivalent of the train shed)by engineers such as Eugène Freyssinet (Fig.7.14) and Pier Luigi Nervi, were praised fortheir architectural qualities and this led to theconcept of the architect/engineer. Theemergence of the architect/engineers (EduardoTorroja, Ricardo Morandi, Owen Williams, and,in more recent times, Félix Candela andSantiago Calatrava are further examples) was asignificant event in twentieth-centuryarchitecture. All these individuals have enjoyedthe same kind of status as the leadingarchitects of their day.

The gap which had long existed betweenarchitects and engineers was not closed bythese engineers operating as architects ratherthan with architects. They have continued anestablished way of working in which thearchitect behaved very much as the leader ofthe design team, with structural engineers andother technical specialists playing a secondaryrole and making little direct and positivecontribution to the visual aspects of a design.It must be said that many engineers are veryhappy to work in this way and to leave thearchitectural aspects of a design to architectsand, in appropriate circumstances, a goodbuilding may be the result.

In the late twentieth century, however, adifferent way of working also becameestablished: certain groups of architects andengineers evolved highly collaborativerelationships, working in design teams ofarchitects, structural engineers, servicesengineers and quantity surveyors, in whichbuildings were evolved through a discursiveprocess. In this very close type of workingrelationship, all of the professionals involvedcontributed to the evolution of a design which

emerged as a truly joint effort. It was thismethod of working which made possible thestyle known as High Tech in which structureand services components formed majoraspects of the visual vocabulary of buildings.

The collaborations between architects,such as Norman Foster, Nicholas Grimshaw,Michael Hopkins and Richard Rogers withengineers such as Ted Happold, Tony Huntand Peter Rice, have been particularlyeffective. The working methodology involvedregular discursive meetings of the designteams in which all aspects of the design werediscussed. The closeness of thecollaborations was such that often, inretrospect, it was not possible to attributemany aspects of the final design to anyparticular individual28.

It was in this spirit that the best twentieth-century examples of ornamentation of structurewere produced (for example Reliance Controls(Fig. 7.4) and the Waterloo Terminal (Fig.7.17)). The genre has continued into the twenty-first century with buildings such as theNational Botanical Garden of Wales (Fig. 7.53)by Foster and Partners with Anthony HuntAssociates, and the Eden Project (Fig. 7.54) byNicholas Grimshaw and Partners with AnthonyHunt Associates. In the latter cases (and this isalso true of the earlier Waterloo building), acomplexity of form has been accomplishedwhich depends on the use of state-of-the-arttechniques of computer-aided design. Thistype of architecture is a strand of Modernismwhich has retained its vitality through theperiod in the late twentieth century in whichPostmodernism and Deconstruction have beenfashionable (both of these being examples ofstyles in which much less creativerelationships between structure andarchitecture have occurred29).

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28 The design team methodology was especially favouredby Tony Hunt who carried out work with all of theleading High-Tech architects; see Macdonald A. J.,Anthony Hunt, Thomas Telford, London, 2000.

29 Most Postmodern architecture falls into the categorystructure accepted while Deconstruction is mainly structureignored.

The buildings in which the design-teammethodology was used are generally regardedas belonging to the High-Tech school. Thesituation is, however, more complex, as morethan one version of the relationship betweenstructure and architecture is discernible inHigh Tech. Many of the High-Tech buildingshave in fact been designed by traditionalmethods, with the architect attendingprincipally to visual and stylistic issues and theengineer confining his or her actions mainly tothe technical details of the structure. As hasbeen shown, the design of buildings such asthe Centre Pompidou was driven principally byvisual agendas in which the architects must beregarded as having operated very much as theleaders of the design teams.

Where truly collaborative relationshipshave occurred, however, the kind ofrelationship between architectural andstructural thinking which existed in antiquityand the Gothic period has been re-captured.In historic architecture, this existed in theform of the ‘master builder’. The present-daydesign team, operating in a truly collaborativeway and using state-of-the-art techniques ofcomputer-aided design, as with Grimshaw andHunt at Waterloo, is the modern equivalent ofthe master builder.

Three types of relationship betweenarchitects and engineers are currently in play.

In the overwhelming majority of Modernbuildings, the relationship between architectsand engineers which prevails is that whichbecame established from the ItalianRenaissance, namely a situation in which thearchitect determines the form of a building andsets the visual agenda, and the engineer actsprincipally as the technician who ensures thatit performs adequately in a technical sense.This type of relationship between architectsand engineers predominates in all of the sub-styles of Modernism including Postmodernismand Deconstruction.

A second type of relationship occurs wherethe architect and the engineer are the sameperson. Several prominent figures haveoperated in this way from the twentiethcentury onwards, including August Perret andRobert Maillart at the beginning of the century,Pier Luigi Nervi, Eduardo Torroja, OwenWilliams and Félix Candela in the mid-twentieth century and Santiago Calatrava atthe end of the twentieth century and in thepresent day. All of these architect/engineershave produced buildings in which thestrategies involved have been those of structureas architecture, structure as form generator orornamentation of structure. Their most memorablebuildings have been long-span enclosures inthe language of the form-active vault or tensilestructure. The aesthetic agenda has been


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Fig. 7.53 National Botanical Garden of Wales, 1999;Foster and Partners, architects, Anthony HuntAssociates, structural engineers. This innovative single-layer dome is a toroidal form executed inone-way-spanning tubular steel arches, of varying span,with orthogonal linking elements. Built form of thiscomplexity in steelwork was not possible before the ageof computer-aided design.

Fig. 7.54 The Eden Project, Cornwall, UK, 1999; NicholasGrimshaw and Partners, architects; Anthony HuntAssociates, structural engineers. The complexity of formmade possible by computer-aided design has brought intobeing a new generation of metal and glass structure.

relatively simple – the appreciation of abuilding as a work of technology.

A third type of relationship betweenarchitects and engineers, that of a trulycollaborative partnership, re-emerged towardsthe end of the twentieth century. This hasinvolved engineers and architects co-operatingfully over the design of a building in a waywhich had not occurred since their equivalentscreated the cathedrals of medieval Gothic. Thebest of the buildings of High Tech have beendesigned in this way.

In the present day, this third category ofrelationship is producing a new kind ofarchitecture of great geometric complexity.The train shed at Waterloo Station by Huntand Grimshaw (Fig. 7.17) is an early example.This building may appear to be simply atwentieth-century version of the nineteenth-century iron-and-glass railway station, withrecent technical innovations such as weldablecast-steel joints. It may also appear to be HighTech. In fact, the steelwork possesses a levelof complexity which could not have beenaccomplished before the age of computer-

aided design and which is suggestive of thecomplexity of a living organism, one of theappropriate metaphors for the philosophies ofthe emerging organicist paradigm. Although,therefore, this building may be seen as adevelopment of the High Tech style, it issignificantly distinct to merit a different name,perhaps ‘organi-tech’. The same could be saidof the dome at the National Botanical Gardenof Wales (Fig. 7.53) by Foster and Partnerswith Anthony Hunt Associates, and of theEden Project (Fig. 7.54) by Nicholas Grimshawand Partners, also with Anthony HuntAssociates.

The realisation of the complex organic or‘land-form’30 shapes of these buildings givesappropriate visual expression to thesophistication of contemporary technology.They also provide ‘intimations’ in severalsenses of what might be involved in a ‘re-constructive’ post-modern architecturalpractice31 even while they remain linked to theModernist agenda concerned with thecelebration of technological progress.

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30 This term was used by Charles Jencks in an article inJencks, C. (Ed.), New Science = New Architecture?, AcademyEditions, London, 1997, in which he discussed the non-linear architecture of architects such as Eisenman,Gehry, Koolhaus and Miralles.

31 See Gablik, S., The Re-enchantment of Art, Thames andHudson, New York, 1991.

Addis, W., The Art of the Structural Engineer,Artemis, London, 1994.

Ambrose, J., Building Structures, John Wiley, NewYork, 1988.

Amery, C., Architecture, Industry and Innovation: TheEarly Work of Nicholas Grimshaw and Partners,Phaidon, London, 1995.

Baird, J. A. and Ozelton, E. C., Timber Designer’sManual, 2nd edition, Crosby Lockwood Staples,London, 1984.

Balcombe, G., Mitchell’s History of Building,London, Batsford, 1985.

Benjamin, B. S., Structures for Architects, 2ndedition, Van Nostrand Reinhold, New York,1984.

Benjamin, J. R., Statically Indeterminate Structures,McGraw-Hill, New York, 1959.

Billington, D. P., Robert Maillart, MIT Press,Cambridge, MA, 1989.

Billington, D. P., The Tower and the Bridge, BasicBooks, New York, 1983.

Blanc, A., McEvoy, M. and Plank, R., Architectureand Construction in Steel, E. & F. N. Spon,London, 1993.

Blaser, W. (Ed.), Santiago Calatrava – Engineering Architecture, Borkhauser Verlag,Basel, 1989.

Boaga, G. and Boni, B., The Concrete Architecture ofRiccardo Morandi, Tiranti, London, 1965.

Breyer, D. E. and Ark, J. A., Design of WoodStructures, McGraw-Hill, New York, 1980.

Broadbent, G., Deconstruction: A Student Guide,Academy, London, 1991.

Brookes, A. and Grech, C., Connections: Studies inBuilding Assembly, Butterworth-Heinemann,Oxford, 1992.

Burchell, J. and Sunter, F. W., Design and Build inTimber Frame, Longman, London, 1987.

Ching, F. D. K., Building Construction Illustrated,Van Nostrand Reinhold, New York, 1975.

Coates, R. C., Coutie, M. G. and Kong, F. K.,Structural Analysis, 3rd edition, Van NostrandReinhold, Wokingham, 1988.

Conrads, U. (Ed.), Programmes and Manifestos onTwentieth Century Architecture, Lund Humphries,London, 1970.

Corbusier, Le, Five Points Towards a NewArchitecture, Paris, 1926.

Corbusier, Le, Towards a New Architecture,Architectural Press, London, 1927.

Cowan, H. J., Architectural Structures, Elsevier,New York, 1971.

Cowan, H. J. and Wilson, F., Structural Systems,Van Nostrand Reinhold, New York, 1981.

Cox, H. L., The Design of Structures of Least Weight,Pergamon, London, 1965.

Curtis, W. J. R., Modern Architecture Since 1900,Phaidon, London, 1982.

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Chapter 1

Selected bibliography

Documents

Structure and architecture - OpenCourseWareocw.upj.ac.id/files/Textbook-ARS-205-TEXTBOOK-10-STRUKTUR-DA… · • ornamentation of structure • structure as ornament • structure