Study of Low Strength Pile Composite Foundation Deformation & Stability Calculation Method

A group of deformation and stability calculation equations on the low strength pile (LSP) composite foundation is deduced from the LSP composite foundation deformation model. The stress-strain compatibility equations are yielded, in which the interactions among the pile, soils and cushions are considered. At the same time, the pile-soil stress ratio and the equal-settlement-surface (ESS) analytical solution are also yielded. Furthermore, the pile and its surrounding soil stress distribution regulation, compression deformation, the up-pricking-deformation of the cushion and the under-pricking-deformation of the subsoil are all obtained. Through the summary of the composite foundation subsoil settlement and the soil among piles compression deformation, the whole settlement of the composite foundation is deduced. In the above equations, the pile stability and flexibility are analyzed using elastic foundation beam theory. The methods put forward here can be a significant reference for the future research and design of the LSP composite foundation.