2016-03-11
Geotechnics
Tunnels and underground constructions
- General contractor: ADIM Ouest
- Client: GTM Ouest
- Project Management: INGEROP/ANTEA GROUP/ENET DOLOWY
- Assignment: G2 & G4
- Total cost of work: €66k excluding tax
- Completion date: since 2013
PROJECT DESCRIPTION AND CHARACTERISTICS
The study carried out by GEOS Ingénieurs Conseils enters into the project of building a tunnel under the river Vannes, at the site known as Kérino, replacing the existing mobile bridge.
This route includes the construction of a 250m sub-fluvial cut-and-cover tunnel and two access hoppers.
ASSIGNMENT
GEOS Ingénieurs Conseils conducted the G2 project studies and geotechnical implementation supervision G4, within the meaning of standard NF P 94-500.
These studies particularly addressed the following points:
- Complementary geotechnical investigations,
- Note on general geotechnical assumptions,
- Analysis of slope stability for access hoppers,
- Evaluation of pumping flows both in the works and final phase,
- Evaluation of modules of vertical reaction,
- Supervision of the cofferdams’ Execution Studies.
2016-03-10
Tunnels and underground constructions
- General contractor :GRT Gaz
- Assignment: Execution Study G3
- Total cost of work: €34k excluding tax
- Completion date: 2014-2015
PROJECT DESCRIPTION AND CHARACTERISTICS
The study carried out by GEOS Ingénieurs Conseils constitutes a part of the installation of a gas pipe Ø 1200 between the communes of Cuvilly and Betz in the department of Oise. The pipeline crosses SNCF tracks underground at five points in the communes of Rouvillers, Houdancourt, Rully, and Ormoy-Villers.
The technique used for the five crossings is the use of a micro-tunneler in lengths of about 40m and at depths between 4 and 6m.
ASSIGNMENT
GEOS’s mission was to carry out partial geotechnical Design Studies (G3 within the meaning of the NF P 94-500 standard of November 2013) for five underground crossings of SNCF tracks, using a micro-tunneler. These studies addressed, in particular, the following points:
- Analysis and synthesis of available geotechnical data,
- Identification of the hazards and geotechnical constraints of project implementation,
- Definition of the principles of preparatory work to be carried out before execution,
- Study of the influence of digging on SNCF tracks: estimation of settlement with an analytical method and of finite element with a numerical method,
- Analysis of the construction conditions and dimensioning of the foundations of the isolating stations,
- Calculation of the settlements induced by the drawdown of the groundwater on the level of the SNCF tracks,
- Definition of excavation solutions to limit the impact on the tracks.
2016-03-10
Tunnels and underground constructions
- Client: ADELAC (the concessionary for the A41 North)
- Assignment: Assistance to Project Management
- Total cost of work (total project): €187k excluding tax
- Completion date: 2006-2008
PROJECT DESCRIPTION AND CHARACTERISTICS
The study carried out by GEOS Ingénieurs Conseils constitutes a part of the construction of the highway A41 North, section Geneva (Switzerland) – Annecy (Haute-Savoie – France).
The characteristics of the project are as follows:
- Two-tube tunnel, 3,000 m long,
- Tunnel dug with cut-and cover tunneling technique Ø = 11.80 m in molasses.
ASSIGNMENT
GEOS acted as an Assistant to the Project Manager, which included:
- external control of design studies (EPOA, APOA);
- preparation of approval decisions;
- auditing of execution and work studies;
- an expertise mission to the Technical Department.
2016-03-10
Geotechnics
Tunnels and underground constructions
- Client: Local Group Coopération Transfrontalière (G.L.C.T.)
- Assignment: Complete project management (AVP, PRO, ACT, VISA, DET, AOR)
- Total cost of work: € 463k
- Completion date: 2006-2010
PROJECT DESCRIPTION AND CHARACTERISTICS
The project involves building a sewage disposal tunnel between St Genis Pouilly in France and Choully in Switzerland.
The project consists of:
- a 3,000m long gallery, Ø 2,500 m;
- 6 collectors Ø 1,000 to 1,500 with a cumulative length of 778m;
- 4 access wells.
ASSIGNMENT
GEOS Ingénieurs Conseils carried out the project management on behalf of the Local Group Coopération Transfrontalière (G.L.C.T.)
The studies included the following:
- geotechnical supervision of the works, tunnel cutting face description;
- all the missions of the MOP law (AVP, PRO, ACT, DCE, VISA, DET);
- AMO, Schedule management and bi-national aspects (customs, taxation, environment, social law, …).
2016-03-10
Tunnels and underground constructions
- Client: SOCIETE DU GRAND PARIS
- Project Management:GROUPEMENT SETEC/INGEROP
- Assignment: Concept studies in phases AVP and PRO
- Total cost of works: €868k (firm order)
- Completion date: 2013-2018
PROJECT DESCRIPTION AND CHARACTERISTICS
The study carried out by GEOS Ingénieurs Conseils constitutes a part of the project of construction of line 15 of the metro “Grand Paris Express”.
– Technical characteristics :
- The tunnel trajectory includes a tunnel Øi = 8.8 m of 4,000 m, dug with a cut-and-cover tunneling method, including three passages under the Seine,
- The works are a part of the geological context of the Senonian chalk,
- Construction of the entrance shaft of the cut-and-cover tunnel, Pont de Sèvres and Issy RER stations as well as the ancillary works.
ASSIGNMENT
As part of its participation, GEOS acts as a subcontractor of INGEROP.
GEOS participates in the project management of the civil engineering of the western section of lot 3 between Pont de Sèvres and Fort d’Issy / Vanves / Clamart.
GEOS conducted the Pre-Project and Project Studies.
These studies addressed, in particular, the following:
- Geotechnical design of stations
- Geotechnical design of the tunnel
- Interaction with existing structures.
