Responses of retaining wall to pre-excavation dewatering under staggered layout of dewatering wells

Abstract

Pre-excavation dewatering (PED) is an important stage in deep excavation in soft ground with high groundwater level. The PED-induced deformations of retaining wall and surrounding environment can reach centimeter level. However, the method to control this deformation has not been yet proposed by the traditional pit design theory and relevant research. In this paper, a countermeasure, which is called as staggered layout of dewatering well, is proposed. In this method, it is recommended that deeper wells and smaller spacings of neighboring wells are employed near the retaining wall. The numerical results show that this method can effectively limit the PED-induced wall deflection.