Agent Access 
Dry dock No.1 in Brest is the smallest and oldest dry dock of the Brest commercial harbour. Built in the 1900s for the ships of that period, the structure had become complex to use to repair current ships. The project led by “DDE du Finistère” (local authorities) hence consisted in widening and fitting it out.
The geotechnical soil-testing campaign led in 2004 allowed to describe the dock walls, raft and surrounding soils, and to assess the reliability of the archive data relating to the the structure’s history. The hydraulic regime according to tides was also studied via continuous monitoring of piezometers and interstitial pressure cells locaed in the dock’s masonry (walls and raft).
These diagnostic elements allowed to rule in favour of the contruction of diaphragm wall behind the South dock wall, that would be demolished subsequently.
The main issues involved:
- Diaphragm wall embedment into highly heterogeneous soils and fractured rock, and connection between the diaphragm wall and the dock walls,
- widening of the raft and its connection with the new wall,
- stability of the dry dock entrance with a dissymmetrical shape (after works),
- check of the global structure stability and of its hydraulic regime.
Terrasol’s achievements:
As a consultant for the Project Manager, TERRASOL achieved the following:
- Summary of available archive documents;
- Definition of the soil-testing campaign and comparison between observations and archive documents;
- Technical recommendations for widening works.
- From 2005 to 2007, TERRASOL acted as consultant of the Project Manager for project design, preparation of tender documents, and works supervision.
