4. Retaining walls. Special provisions

Buried basement walls

In this case, the excavation required to build the basement leaves a wedge-shaped space to be filled in between the more or less steep slope and the basement wall: backfilling must therefore only be carried out once the high basement floor essential to the wall's stability has been built.

However, in the case of steep slopes, and especially in clayey soils, there is a significant risk of landslides, which calls for precautions to be taken: backfill immediately after laying the high floor or, failing that, drain the slopes upstream and cover them with tarpaulins, etc., in order to eliminate the risk of landslides.

In all cases, the backfill must be made of permeable material, placed manually or with light machinery. It should also be remembered that the materials used...