The Petit Rhône

While 2010 was marked by a slightdecrease of our activity due to thesudden cancellation of a number of

major projects for socio-political reasons, 2011is a year of strong increase.Notable examples include the East-EuropeanHigh-Speed Line (or “LGV”; the construction ofthe Saverne tunnel has already begun),the “Bretagne – Pays de Loire LGV” (soilinvestigations are underway), but also buildingrenovation projects that re-use existingfoundations with extra reinforcement (thedepots on Boulevard Mac Donald and theJussieu Faculty in Paris). We could also mentionthe geotechnical services we provide to supportthe projects of companies operating in the “oiland gas” sector in various regions of the world,from Australia to Russia or Latin America.

We will present the progress of these projects infuture issues. This issue of the TERRASOLnewsletter illustrates some of our projects thathave marked our Srst semester 2011, and thevariety of our missions: project types, regionsof the world, type of services.

This year will also be important for our softwaredepartment: the development of AMRetain, onrequest from ArcelorMittal, was Snished in may2011. And major updates of Foxta and K-Reawill be released in autumn 2011. It should bepointed out that both AMRetain and the newK-Rea version are in compliance with the NF P94-282 standard (French standard for theapplication of Eurocode 7 to retainingstructures).

The National ASIRI Project, in which BrunoSimon has performed admirably as technicalmanager, will also be completed in 2011 withthe publication of recommendations offeringclear conclusions to more than four years ofresearch.

TERRASOL thus proceeds with its developmentand focuses on the answers to bring to theincreasingly varied requests of our customers.We are more than ever willing to anticipate thestrategic, technological and regulatory changesaffecting geotechnical engineering, and toparticipate through our engineers to thegeotechnical scientiSc community.

A. GUILLOUXPrésident Directeur Général

In 2009, SYMADREM (“SYndicat Mixteinterregional d’Aménagement du Deltadu Rhône et de la Mer”) entrusted the

TERRASOL / Hydratec group with acontract for carrying out the outline studiesand preliminary design for reinforcementand partial geometrical modiScation of 18km of dikes along the left bank of the PetitRhône (downstream from Arles).SYMADREM is an inter-regional associationcreated by SIDRHEMER, itself founded in1996 following the never-to-be-forgottenTooding that took place in the Camarguearea.These dikes reinforcement studies andworks fall within the scope of the Toodingsection of the “Rhône Plan” which aims toachieve the following:• Reduce Tooding by acting on causes,• Reduce vulnerability by acting on stakes,• Adapt to living with the risk by developing

an understanding and appreciation of therisks involved.

To this end, the contract awarded to theTERRASOL / Hydratec group consists incarrying out preliminary studies aiming togeographically deSne the failure risks andquantify these risks, and to determine thereinforcements needed and measures to betaken in areas where there is clear evidenceof danger.

The speciScity of this type of mission lies inthe way it is broken up into multiple phases,each of them subject to validation by acommittee of experts:• Phase 1: historic background and visual

inspection, GIS,• Phases 2 and 3: systematic survey of

dikes and areas identiSed for geometricalmodiScation,

• Phase 4: detailed investigations,• Phase 5: deSnition of failure risks,• Phase 6: preliminary report,• Phase 7: preliminary design of reinfor-

cement works,• Phase 8: preliminary design report.

When compared with other work sectionsawarded to hydraulic engineers, theparticularity developed by the Terrasol /Hydratec group was to have the groupmanaged by the geotechnical team.This type of “packaging” was unanimouslywelcomed by experts as a way of ensuringquality and a technical appreciation of theways in which dikes are expected to fail.The proximity of Terrasol and Hydratecwithin the Setec Group buildings in Lyonensured that work was carried out rapidly ina manner fully adapted to the variousphases.Preliminary studies are now in their Snalphase and preliminary design studies willbegin this summer.

J. Drivet

LaLettreJune 2011 - n °18

The Petit Rhône earth dikesEdito

Works on the A89 motorway sectionbetween Balbigny and the Viollaytunnel have been going on since 2009.

Within the scope of constructing these 14.5kilometres of motorway that include threeviaducts and 15 standard civil engineeringstructures, TERRASOL, having carried out thegeotechnical part of the preliminary and detaileddesigns, and contractor bid studies, is nowproviding geotechnical assistance during the siteworks phase to Setec TPI, project manager forearthworks and standard civil engineeringstructures and owner assistant for the viaductswith a “design and build” contract.Currently, and despite bad winter weather, theearthworks and standard engineering structuresare almost completed and Sve out of the sixviaduct slabs have been cast.The geological context, essentially highlytectonised volcanic rock, required a few minoradaptations during the works phase to take intoaccount large variations of substratum alterationand fracturing over very short distances.For example, it was necessary to rebuild the slopeunder a structure abutment as it presented anerratic alteration that endangered the structurestability.These adaptations were carried out very rapidly,and in coordination with the group of contractorsand the project manager, in order to avoidperturbating the works schedule. Terrasol’sreactivity contributed to maintaining theschedule.

A-L. FaurouxJ. Drivet

TERRASOL, moved on June 27th to newofSces in Paris and thus joined the otherParis ofSces of the Setec group.Please take note of our new coordinates:

TERRASOLImmeuble Central Seine42-52 quai de la Râpée75583 Paris Cedex 12 - France

Tel.: +33 (0)1 82 51 52 00Fax: +33 (0)1 82 51 52 99Email: info@terrasol.com

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-2- -3--1- A89-2- Gabes-3- Jenner tunnel, tunnel face-4- Jenner tunnel, geotechnical proSle-5- Majunga building-6- Sheraton Park project

Central Seine

A89 Balbigny/Viollay

Gabes, Tunisia

Storage depot

Loire

Within the scope of the construction of anew liquid hydrocarbon storage depot inGabes (Tunisia), TERRASOL, working with

TERRASOL TUNISIA, was chosen by ENTREPOSECONTRACTING to carry out the construction designfor six storage spheres, each with a 4,000 m3capacity and, in particular, the foundations design.The spheres are protected by a sand-Slledreinforced concrete shell. Each sphere, weighingaround 10,500 tons, is seated on a general annularraft with a 24 m external diameter. These rafts aresubject to very strict admissible settlementconstraints (maximum absolute settlement: 15mm).

Geotechnical surveys revealed a succession ofsandy and then clayey levels, with three referencelayers: loose Sne sand (almost subject toliquefaction) between 5 and 10 m deep, verycompact Sne sand from 10 to 22 m, and stiff claywith gypsum nodules below 24 m. BoreholesidentiSed a large number of decompressed levelsand compressible layers within this clay,corresponding to gypsum dissolution pockets.This major concern as well as the sensitivity of thestructure to settlement led us to focus on thefoundation principle to be adopted. We Snallychose a piled raft foundation solution with a raftand short piles anchored into the compact Snesand. As a result, each sphere will rest onfoundations comprising 150 piles, each with adiameter of 0.6 m and a length of 13 m.The chosen execution technique is the CFA(Continuous Flight Auger) technique, equivalent toa type II hollow auger, and locally available.The foundation works, supervised on site byTERRASOL TUNISIA, began in March 2011 at anaverage construction rate of 10 to 12 piles a day.

M. ReboulH. Le Bissonnais

Construction of the Majunga high-risebuilding in the “La Défense” business districthas begun and, on what is probably the last

free plot remaining among the existing high-risebuildings and skyscrapers, the Eiffage Constructionand Botte Fondations teams have started work: jet-grouting, injections, soldier piles and “Parisian”piles, etc.Over the four years that TERRASOL has beenfollowing the project with Setec tpi, a wide rangeof problems have been resolved. The engineeringstudies have had to deal with issues as varied asthe former Calcaire Grossier quarries located underthe plot, the retaining structure around theexcavation, the raft foundation and the impact ofthe works on neighbouring buildings.

In particular, TERRASOL chose to use Tasplaqsoftware to estimate the settlement caused by thebuilding. This has been estimated as approximately9 cm below the core after 50 years of operation.The “G3” level study, carried out by Fugro usingPlaxis 3D software, shows the successful matchingof these two approaches when consideringsettlements.TERRASOL is now responsible for the geotechnicalsupervision of works (“G4” mission) as well as theexternal inspection of the construction designdocuments (“visa”).

For the time being, everything is still taking placebelow groundlevel, and earthworks have not yetbegun. We will keep you informed about Majungabuilding in a later issue of this Letter!

C. Lefèvre

The Jenner tunnel is a 535 m long two-trackunderground structure for the Srst tramway tobe built in Le Havre, linking the lower part of

the city to Place Jenner located in the upper part.It is constructed in parallel with and fairly close tothe existing road tunnel.

The overburden varies in depth from 35 m to 6 mfor an excavated section of around 60 m².

The tunnel is excavated with the “traditionalmethod” using a cutter machine equipped with amilling head weighing several tons: excavationbegan end-January 2011 and is scheduled forcompletion for end-2011.Spie Batignolles commissioned TERRASOL to carryout an additional geological survey and geologicallymonitor the tunnel excavation.

The main concern about the excavation phase wasthe installation of heavy supports (steel ribs,sprayed concrete, umbrella arch and face bolts, aswell as local counter ribs on raft) to compensatefor unfavourable geological conditions (karstic orweathered areas) anticipated over most of theroute while it may be assumed that the facies beingcrossed is largely compact chalk considered as arock.

The tunnel is located next to a plateau dug outfrom Cenomanian chalk, covered over a decametricthickness by Tint clay and, locally, plateau loam.The beginning of the excavation conSrmed thepresence of largely sound chalk, although with thepresence of small karsts requiring “forepolling” typepre-support.

L. Casasola

Within the scope of constructing anunderground car park (2,000 parkingspaces) and a 73,000 m² landscaped park

positioned in front of the Sheraton Hotel in Doha,the VINCI CONSTRUCTION GRANDS PROJETSStructural Design Department entrusted TERRASOLwith a mission to study a solution using a micropileanchored raft-type foundation. More speciScally,the study, based on numerical modelling (PLAXIS2D), aimed to establish the forces in the micropilesrequired to absorb the hydrostatic pressure (tensionpiles) while taking into consideration the shrinkageof the concrete raft.

The car park raft is positioned in compact limestoneformations located approximately 20 m belowgroundlevel and 15 m below the water table.

Modelling using several 2D proSles led to thefeasibility of the micropile solution being validated.The modelling also better deSned the installationconditions for this type of solution insofar as thefollowing points were concerned:

• Adaptation of the micropile grid to match thespeciSc positioning of the piles,

• Minimal steel section used for the micropiles,• Raft – micropile connection system.

K. V. NguyenP. Chalivat

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Majunga high-rise buildingJenner tunnel

Le Havre Doha, Quatar

Sheraton Park project

La Défense

www. terrasol.com

Immeuble Central Seine42-52 quai de la Râpée75583 Paris Cedex 12 - France

Tel.: +33 (0)1 82 51 52 00Fax: +33 (0)1 82 51 52 99Email: info@terrasol.com

Immeuble L’Orient10, place Charles Béraudier69428 Lyon Cedex 03 - France

Tel.: + 33 (0)4 27 85 49 35Fax: + 33 (0)4 27 85 49 36Email: lyon@terrasol.com

Rhône-Alpes

2, rue Mustapha AbdessalemEl Menzeh2037 Tunis - Tunisie

Tel.: + 276 71 23 63 14Fax: + 276 71 75 32 88Email: info@terrasol.com.tn

Tunisie

• Gestion de l’aléa karstique sur les ouvrages en terre de la ligne ferroviaire Gautrain en Afrique du Sud (A. Guilloux et A. Bergère) – Symposium International Georail 2011 - Paris, Mai 2011

• Déformations excessives d’une plateforme ferroviaire suite à une saturation du corps de remblai (A. Guilloux et A. Bergère) – Symposium International Georail 2011 - Paris, Mai 2011

• Optimisation des plateformes de tramway à partir d’une modélisation tridimensionnelle en éléments Snis(H. Le Bissonnais et M. Reboul) – Symposium International Georail 2011 - Paris, Mai 2011

• Retour d’expérience sur les études et le creusement du tunnel de Chavane – Terrassement et excavation dans les marnes gonTantes(P. Legrand, C. Lefèvre et S. Curtil) – Symposium International Georail 2011 - Paris, Mai 2011

• South Toulon Tunnel: Analysis of an instrumented section (JP. Janin, D. Diasl, R. Kastner, F. Emeriault, A. Guilloux et H. Le Bissonnais) – Symposium TC28 IS Roma - Rome, Mai 2011

• Settlement monitoring and tunneling process adaptation – case of South Toulon Tunnel(JP. Janin, D. Dias, R. Kastner, F. Emeriault, A. Guilloux et H. Le Bissonnais) – Symposium TC28 IS Roma - Rome, Mai 2011

Plaxis 3D

TERRASOL recently achieved 2 major studies using PLAXIS 3D:modeling of a very high and complex excavation in Monaco (TourOdéon, please refer to Plaxis bulletin) and modeling of Toulon Tunnelexcavation (PhD jointly with INSA de Lyon).

Agents – Focus on Mexico

GEO INGENIERIA ALFVEN (Mr Alfonso A.MANILLA) has been our agent in Mexico forseveral years now. His territory has beenprogressively extended to most countries ofSouth America.He has recently spent a few days atTERRASOL and we are presently preparingtogether a training session about TERRASOLsoftware (Foxta, Talren, K-Rea, etc) to be heldin Mexico in 2012.

AMRetain software

TERRASOL developed for ArcelorMittal the AMRetain program,enabling for the checking of ArcelorMittal sheet pile walls (single oudouble walls, cantilever or anchored walls). This software also includesvarious checks according to the French standard NF P 94-282(application of EC7 for retaining walls calculations): checking ofpassive earth pressures, balance of vertical forces, Kranz check(equilibrium of anchoring block).AMRetain was just Snished and we will now make the same featuresavailable in our commercial software K-Rea.

64bit compatibility

Talren 4, K-Rea and Straticad are now available for 64bit operatingsystems (Windows® XP/ Vista / 7).Note: standalone hardlocks need to be exchanged for new ones inorder to be compatible with 64 bit OS. Please contact us for moreinformation.

Plaxis 3D 2010.02

Plaxis 2D 2010.01

Talren 4 v2.0.4

Foxta v2.0.2

K-Rea v2.4.0

Tunren v1.05

Straticad v1.2

International Events

• Geogrup, our agent in Turkey, organized a Talren training session in Istanbul in April 2011 withabout 15 participants.

• TERRASOL had an exhibition stand during the International Symposium GEORAIL in May 2011,and represented both Terrasol and Plaxis software.

• TERRASOL TUNISIA will have a stand representing both Terrasol and Plaxis software duringthe next African Regional Conference in Maputo, July 2011.

• And we will have a stand during the next European Conference on Soil Mechanics andGeotechnical Engineering in Athens, September 2011.TERRASOL stand, Géorail 2011

PLAXIS 3D model for the Monaco Odéon project

Software Department

Recent publications

Up-to-date vers ions