The Composite Ground Finite Layer Method and its Application to Pile Foundation Analysis

Abstract

To study the influence of a foundation structure on the ground, the finite layer method of composite ground is derived based on the finite layer method (FLM) theory of the semi-analytic numerical method and the force method principle of elastic material, which is used to analyze a layered ground including multiple internal constraint planes. By simplifying a pile body as a solid constraint composed of four side plane constraints, the composite ground FLM is applied to solve the displacement and stress field of the ground. The change of the ground displacement and stress caused by the addition of a single pile constraint are then discussed, and the influence rules of a pile position on the ground displacement are also determined. Finally, the necessity, rationality and validity of the composite ground FLM are demonstrated by the model test examples of a single pile and pile raft foundation.

Analysis of instantaneous surface settlement of tunnel construction in composite stratum based on semi-analytical method

“…Under such circumstances, the theoretical analysis of surface settlement may be solved successfully if an analysis method can simulate the real properties of composite stratum, and then it is possible to work out the me-chanical characteristics of the stratigraphic space during shield tunneling. Usually, the finite layer method is used to settle the mechanical analysis of uneven ground [31,32]. Therefore, the finite layer model is applied to simulate the composite stratum, and the finite layer method is used to find out the relationship be-tween the effective thrust and surface settlement when shield tunneling.…”

“…are imposed inside the area. In this way, the extended finite layer method [31] is possible to work out the stress field and displacement field of the composite stratum generated by various loads.…”