Soil arching effect of composite piles supporting foundation pits based on mechanical model and photoelastic experiment

Abstract

In this study, the analytical solution of soil stress behind a composite pile and the arch height of the soil was derived using a mechanical model of a composite pile supporting the foundation pit. The mechanical model was developed based on the theory of uniform load on semi-infinite space in elastic mechanics. The analytical solution was validated through a photoelastic experiment and finite element numerical simulation, and the soil stress behind the composite pile was calculated. The stress visualization of the composite pile supporting the foundation pit with different pile diameters and spacings was realized through photoelastic experiments. The empirical relationship was established between the inner and outer arch heights, load, pile diameter, and spacing. A finite element simulation was performed to examine the influence of small pile diameter and spacing on the soil displacement and lateral stress coefficient. This study provides an important reference for studying the soil arching effect of composite piles supporting foundation pits.