ABSTRACT
Retaining structures for excavations in urban areas generally comprise prestressed ground anchors in order to prevent soil displacements which could be detrimental for buildings located in the vicinity. The paper deals with the use of the finite element method for evaluating the soil displacements during and after the excavation. After discussing the common simplifications on the soil behaviour and on the geometry (2D modelization) for the analysis of multi-anchored walls, the author presents the finite element modelling of an experimental fully instrumented soil nailed wall constructed as part of the french research project Clouterre. The displacements calculated by three codes (Cesar, Plaxis, Flac) are close together and agree fairly well with the measurements. A parametric study shows that the most important parameters are the cohesion and Young modulus of the soil as well as the Young modulus of the grouted nails.
