Model tests and numerical simulation of braced excavation in sandy ground: Influences of construction history, wall friction, wall stiffness, strut position and strut stiffness

Abstract

Two-dimensional model tests and elastoplastic finite element analyses for excavation problems with a braced wall are performed to investigate the influence of construction history, wall friction, wall stiffness and the struts on the ground movements and the earth pressures on the wall. Test results show that the surface settlements of the backfill and earth pressure on the wall depend on the deflection process of the wall, even if the final wall deflections are the same. The wall friction, wall stiffness and the position and stiffness of strut significantly affect the earth pressure on the wall and the ground movement including the surface settlements. The computed results, in which mechanical behavior of soil and structure, behavior of interface between soil and wall and the process of excavation were properly taken into consideration, describe well the results obtained in the model tests. Such influence on the deflection of the wall, the earth pressure on the wall and the ground movements has not been evaluated properly in the present design practice.