References

Ivory Coast has launched an ambitious project to safeguard and develop the Cocody lagoon, ideally located below the Plateau district in Abidjan, and threatened by mud and sand silting. The developments comprise a first phase of backfilling in the lagoon to create platforms, which will be developed subsequently, and a marina.

Moroccan company SGTM has been contracted to build the backfill platforms in the lagoon, under joint project management by BNETD and CID, and project owner assistance by MARCHICA.

The complex geotechnical context, with large thicknesses of mud and extremely compressible materials, decided SGTM to call upon the services of TERRASOL as geotechnical expert to get optimal understanding of the geotechnical risks.

TERRASOL has consequently provided expert assessment as needed on part of the works already completed (phase 1), and then design studies on the part under construction (phase 2).

The main issue of these backfilling works is to predict not only the settlements but also the volume of sand replacing the mud that is pushed ahead of it. The phase 2 geotechnical investigations (programme defined by TERRASOL) are currently in progress, and the design phase itself will start when they are completed.

Terrasol’s achievements:

• Complex geotechnical context
• Analysis of geotechnical hazards
• Intervention on two project phases