Back analysis of a deep excavation-pile interaction using 3-D finite element analysis

Abstract

In the course of underground Mass Rapid Transit construction in Singapore, there was a cut and cover excavation that ran parallel to an existing expressway viaduct supported by piles. Engineers are concerned on the effects of excavation-induced soil movement on the adjacent existing pile foundations supporting the viaduct structure and had set stringent deflection limit for the pile caps during and after construction. This paper focuses on the bending moment and deflection responses of the 4-pile groups supporting the viaduct adjacent to the deep excavation. Back analysis was conducted using 3-dimensional finite element analysis and the calculated results were compared against the instrument observations. The results of the comparison reveal that the finite element analysis can predict the pile deflection reasonably well. © 2009 IOS Press.