A construction monitoring using backward analysis in large excavation of foundation pit in Shanghai's soft ground

摘要

Many large excavations in soft ground of Shanghai are carried out recently and excavation depth of some foundation pits is over 16m. Therefore, construction of foundation pit has a great effect on the stabilities and deformations of retaining structure system, nearby buildings, surrounding soft soil ground and underground pipelines. Some serious troubles of project due to incorrect construction sequence occur in the last several years, which result a great economical damage. For reducing the bad influences on surroundings and guaranteeing project safety, a construction monitoring for large excavation of foundation pit is made by use of 2D-FEM backward analysis with staged construction simulation at the first time and thus a deformation forecast is carried out. A case study of foundation pit in soft ground of Shanghai is given and research results show the presented method is more powerful to practical engineering project and can guide project construction.