The application of the Iwan soil model on a deep excavation

Based on the Ivan model, numerical simulations of well documented construction of anchored diaphragm wall supporting the 20 m deep excavation in Berlin sand were carried out. The model incorporates the critical state concept by using two sets of elastic-plastic elements, one set for the volumetric response, and the other for shear. The parameters for the model were derived from laboratory and in-situ tests on Berlin sand, and from data for some well tested sands (Erksak, Toyoura, Portaway, Ticino, Ottawa). The results show that the model is capable of describing well the observed behavior of the diaphragm wall in all construction stages. These results are compared with published results obtained by the advanced MIT-SI model.