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Rehabilitations and expertises

Feasibility study for the modernization of TBILSI metro (BERD funded).

In support of EGIS International, the feasibility study concerns the renovation of 10 stations at great depth, from the point of view of civil engineering, drainage and waterproofing injection works. The rock layer was indeed very fractured and saturated with groundwater.

Following an on-site inventory mission and meetings with the Client (TBILISSI Transport Company) waterproofing solutions through cement /bentonite injections were studied and estimated, with the renewal of the drainage system.

Solutions to replace architectural coatings have also been proposed.

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Rehabilitation of the Essaida Tunnel in Tunis (Tunisia).

Expertise and feasibility study for the rehabilitation of the ancient ESSAIDA tunnel of the SNCFT network in Tunis, to define the requested works for the re-opening and safe operation of the structure. Including cost estimation (2016).


The Essaida Tunnel is located in Tunis, at PK 1 + 550 of the Tunis - Gobaa railway line (formerly known as TA, Tunis - Algiers), operated by SNCFT.

Single track rail structure, built in 1877, length 316 m. Its layout is part of a curve with radius R = 615 m. The lower overburden is 11-12 m and the maximum overburden measures approximately 24 m.

This expertise imposed and concerned considerations and interventions of railway operation, analysis of track conditions and platform waters.


Feasibility study for the renovation of the Metro tunnels in Tibilisi (Georgia)

Expertise and feasibility study, funded by the ADB, for the rehabilitation of existing tunnels finalized to the definition of the further studies and works (2017).


The metro network of the city is made up of two lines which are 27 km long and serve 22 stations, including 20 underground, at great depth (30-40 meters underground).

The first line dates from 1966, the second from 1979, and extension work is underway.

The two metro lines are affected by large inflows of water which infiltrate in tunnels as in stations. In addition it is a very aggressive water (sulfates), dangerous for the concrete.


This expertise imposed and concerned considerations and measures of railway operation, analysis of track conditions and platform waters.

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Rehabilitation of tunnels and cuts of the VAL'TRAM Aubagne - Bouilladisse project (France).

Responsible for Expertise and preliminary study to rehabilitate the 2 old tunnels included on the line, to define the requested works to re-open and operate the tunnels and approaching cuts. Including safety systems upgrade and cost estimatation (2016).


The VAL'TRAM project consists of rehabilitation of the old Valdonne railway for tramway operation. Lenght of the line of approx. 14 km between Aubagne station and Bouilladisse, using the rights-of-way of the abandoned railway line. It includes Roquevaire tunnel, approximately 225 m long and Pont de l'Etoile tunnel, approximately 110 m long, both built in early 1900.  

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