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, …).
