Finite-element analysis of secant pile wall installation

A common practice in the USA for excavation support system design is to assume that the complete support system is ‘wished in place'. This implies that the construction of the in situ wall component and the installation of the supports do not cause any movements or changes in the in situ stress state. However, the installation can cause appreciable changes in the in situ soil stress conditions, which result in significant movements in the surrounding ground. This paper presents the results of efforts to evaluate the factors that influence movements associated with excavation support wall installation, using a series of three-dimensional finite-element models. These analyses demonstrated that soil responses and the processes that produce them are three-dimensional in nature. Thus it can be concluded that fully three-dimensional analyses are required to provide insight into these complex relationships.