Integrated Delivery Empowered by Computational Geometry

Gregor V

ilkner, P

h.D., T

hornton Tomasetti, U

SA

Will L

aufs, D

r. -Ing., IW

E, LEED, T

hornton Tomasetti, U

SA

Geometric

Design Development

The paneling of th

e ro

of s

urfa

ce w

as expected to

yield to

, maintain

and continue all th

ree curved side-lin

es, a

s well a

s in

tegrate with th

e

placement o

f the outer fa

çade m

ullio

ns. T

he goal w

as to

produce an

aesthetically pleasing design th

at w

as also effic

ient in

a way th

at can

be tie

d to

perfo

rmance m

etric

s such as weight, c

ost, c

omplexity,and

enviro

nmental perfo

rmance.

All work related to th

e development of the roof cap geometry

was

carrie

d out in

CATIA / D

P. B

ecause of th

e algorith

mic work approach

all o

perations w

ere scripted using VBA. Im

age (A

) below shows th

e

corre

ct ro

of e

dge and where vertic

al m

ullio

n lin

es fo

rce grid

points of

the roof grid

. Im

age (B) shows a paneling schema that produces

identical p

anels, b

ut it d

oes not y

ield to

the edge geometry

require

d.

Finally, vario

us algorith

ms were studied th

at u

nroll th

e edge verte

xes

into a plane, p

roduce a grid

utiliz

ing m

aster a

nd slave curves in plan,

and m

ap th

e points back into th

e curved surfa

ce (C

+ D).

Moscow International Business Center

Moscow is undergoing an unprecedented

constru

ction boom. Just outside the historic

center o

f the R

ussian capital, “M

oscow-City”

grows on a gigantic site that takes up 1

square kilometer.

The images below illu

stra

te the two model methodology explained

above. T

he C

ATIA and Tekla

models are both used simultaneously

by scrip

ts when c

ontent is

generated. V

ertic

al b

ow tru

sses th

atare

orie

nted norm

al to the surfa

ce of the sloping façade are shown in

their g

eometric

development p

hase in

CATIA (A

), and in th

e physical

model (B

). Similarly, ra

in gutte

rs th

at w

ere in

tegrated w

ith th

eroof

grid

are shown in their geometric

development (C),

where a tube

extru

ded along a 3-D splineis in

tersected w

ith th

e grid

to fin

d th

e

contro

l points fo

r the plate m

ateria

l that m

akes th

e physical gutte

r (D).

Federation Tower Roof Cap

At 3

65m, T

ower A

of F

ederation Tower w

ill be

Europe’s tallest building when completed in

2009. Prim

ary constru

ction of the smaller

Tower B was finished in early 2008. Both

towers fe

ature at th

eir to

ps uniquely shaped,

glazed ro

of stru

ctures.

The

footprin

ts

of

the

twin-to

wers

are

triangular

with

arc-shaped

sides.

Each

tower’s

vertic

al

envelope

tapers

as

it

increases in

height. T

he ro

of c

ap, o

r “Tower

Crown,”

is the intersection of a cylindrical

surfa

ce with the slanted vertic

al part

of the

building envelope. The cap for Tower A is

envisioned to

be m

ade of g

lass and steel, a

s

transparent a

nd elegant a

s possible.

Initia

l Design

The orig

inal design was developed entire

ly in 2-D. T

he im

ages below

show th

e basic geometric

assumptions fo

r the fo

rm of th

e tw

o to

wers

(A + B). T

he paneling grid

lines fo

r the Tower B

roof cap ru

n parallel to

the main directions of curvature (C).

To allow development of an

alternate schema fo

r Tower A

mullio

n points were compiled fro

m 2-D

plans in

to a single 3-D m

odel (D

+ E). T

his approach allows smooth

continuation of vertic

al m

ullio

n lin

es into th

e ro

of surfa

ce.

55.52°

5.93°

185055

56.00°

365.070

120.927

449.459

+420.000

+509.000

221.609

341.675

R54466

67.643

324.757

R24997

204.680

R24997

4910 17046

R24997

R24997

4910 17046

243.566

R106286

R106286

R16539

R2225

103.994

142.880

7816

56225 height of centre of outline tower B

19700

61461

31118

67643 hwight of centre of outline tower B

67.643

19140

62083

10184

36525

22.552

6121

242.399

5030

10184

R58154

8.11°

11780

R104947

R104947

R1049

47

R104947

R104947

R104947

facade outlin

e (id

eal), le

vel 91

R104947

23537

64218

64218

R104947

23537

R30922

R30922

4750

4750

R104952

R104952

1306

1322

20953

20953

R104947

R104947

R10363870189

111822

7420

7378

7420

7378

7173

7296

7296

7173

58534

12

17

18

P ?

A A P ?

17

18

12

17°

facade outlin

e (id

eal), le

vel 11 - 1

9

facade outlin

e (id

eal), le

vel 46

facade outlin

e (id

eal), le

vel 64

19396

3426

69675

65699

facade outlin

e (id

eal), le

vel 83

9153

68554

70189

19396 3407

69669

65699

915368554

ABC

DE

AB

CDEF

The fin

al g

eometry

was slightly adjusted on th

e back edge, to

allow

for 4

0 m

ullio

n lin

es on th

e back fa

ce vs. 3

4 on th

e tw

o sides (E

). With

the grid

in place, assemblies such as rails and tru

sses could be

generated norm

al to

the ro

of surfa

ce and at precise grid

points (F

).

3-D Geometry

(CATIA / D

P)

Virtu

al M

odel

(Tekla)

CNC-Based

Fabrication

Pre-Assembly

Erection

Analysis

(SAP, M

epla)

Detailin

g(Sketches, A

CAD)

2-D Drawings

(ACAD)

Arch. V

ision

Constru

ction

Sequencing

Analysis models were created fro

m either the CATIA or the Tekla

model using tra

nslation routines developed in-house. The images

below show a M

epla

model fo

r stru

ctural a

nalysis of g

lass panes (A

)

and a SAP m

odel fo

r analysis and design of th

e stru

ctural steel (B

).

One of the options to install planar glass panels on our cylindrical

lattic

e is to use wedge-shaped aluminum members glued onto the

glass surfa

ce. A

s m

entioned above, w

e developed options in

2-D (A

+ B) a

nd te

sted th

em locally in th

e 3-D m

odel (C

+ D).

Integrated Delivery

Once detailin

g,

fabrication,

and erection enter

the equation,

complexity reaches a new level. Although we used CATIA to deal

with the challenge of minimizing offsets of planar glass panels,

stru

ctural and façade details were firs

t developed in 2-D and then

tested in

the 3-D Tekla

model –

manually in

selected lo

cations firs

t,

and automatically across th

e w

hole m

odel la

ter. T

he im

ages below

show th

ree approaches of a

ligning glass panels: b

ent (A

), lowered at

top and botto

m verte

xes (B), and lowered only at botto

m verte

xes

(C). Initia

l concept details were modeled in CATIA (D + E), which

proved to be much less effic

ient then using detailin

g techniques

available in Tekla( e

.g. cuts, blends, p

lacing of tru

e 3-D objects.)

AB

CD

AB

AC

B

DE

AB

CD

Integrated Design

Although all g

lass panels and all m

embers of th

e support s

tructure

are geometric

ally unique, their

form

s follow similar development

rules. D

esigning any “ty

pical”detail in

3-D allowed th

e generation of

parametric

components that were then replicated throughout the

whole m

odel. W

e developed a process th

at a

llowed us to

work with

two m

odels simultaneously. W

e used a CATIA m

odel a

s a geometry

hub and carrie

d out th

e physical m

odeling using VBA scrip

t in the

detailin

g softw

are Tekla. T

his approach allowed us to

utiliz

e CATIA’s

superio

r geometry

engine to

automatically generate content in

Tekla.

About th

e Authors

Dr.

Vilkner,

director

of

automation at

Thornton Tomasetti,

is

responsible fo

r firm-wide re

search and stra

tegic development re

lated

to integrated stru

ctural d

esign and building in

form

ation m

odeling. H

is

versatile

expertis

e in

cludes work-flo

w in

tegration th

rough automation

and custom in

teroperability

, advanced collaboration te

chniques, a

nd

complex data stru

ctures. He has in-depth technical knowledge,

including data mining, problem modeling and knowledge exchange

through the APIs of Revit,

Tekla, Digital Project,

AutoCAD ADT,

Rhino, MS Project,

Prim

avera, etc. Dr.

Vilkner holds a Dipl.-In

g.

diploma fro

m University of R

ostock, G

erm

any, a

nd M

. Phil. a

nd Ph.D.

degrees fro

m Columbia University, N

ew York.

Dr.

Wilfrie

dLaufs

is vice president at Thornton Tomasetti

with

responsibility

for specialty stru

ctures within the firm

's building skin

practice. He focuses on the use of new materia

ls, stru

ctural glass

elements, and challenging stru

ctures with complex geometrie

s and

architectural building elements. H

is expertis

e includes th

e application

Abstract

Achieving innovative architectural vision increasingly re

lies on, a

nd is

empowered by, c

omputational g

eometry

delivered th

rough advanced

design softw

are such as Rhino, C

ATIA or G

enerative Components.

On this poster we describ

e a project that applied computational

geometry

techniques extensively to

enable integrated project d

elivery

and allow th

e design te

am to

achieve its

objective fo

r effic

iency and

precision. W

e show how a geometric

process is established and can

be leveraged, not only throughout conceptual design and form

finding, but furth

er utiliz

ed for analysis, detailin

g, fabrication and

constru

ction. The Federation Tower example illu

stra

tes benefits

achieved fro

m early virtu

al p

rototype development, d

igital in

tegration

of in

terdisciplinary design problems, C

NC-based fa

brication, m

odular

pre-assembly of components, a

nd effic

ient in

stallation in th

e fie

ld.

and development o

f softw

are programs to

assist in

stru

ctural fo

rm-

finding and detailin

g th

at a

re integral to

the design esthetic and visual

identity

of s

paces. D

r. Laufs

believes an in

tegrated design approach

comes fro

m th

e unity of a

rchitecture and stru

ctural e

ngineerin

g.He

holds Dipl.-In

g. and Dr.-In

g. degrees fro

m the University of RWTH

Aachen, Germ

any and has worked in Stuttg

art,

London, Bangkok,

New York and on projects on fo

ur c

ontinents.

Acknowledgements

We would lik

e to

extend our g

ratitu

de to

Leonid Zborovsky, p

rincipal

at T

hornton Tomasetti in

charge of th

e Federation Tower p

roject.We

are fu

rther a

cknowledging th

e excellent w

ork of o

ur c

olleagues Brad

Malmsten, Boris Weinstein, and Mario

Claussnitzer. Thanks to our

client,

the Mira

xGroup for

their

continuing support

and their

willin

gness to explore this unconventional roof design. Regards to

Sergey Tchobanand his te

am of a

rchitects fo

r great te

am work and

superb collaboration on th

is excitin

g project.