STUDY ON ULTIMATE BEARING CAPACITY OF TWO-LAYERED SUBSOIL UNDER HORIZONTAL AND VERTICAL LOADING

摘要

To calculate the ultimate bearing capacity of shallow strip footings under horizontal and vertical loading on inhomogeneous soil foundation is very valuable and significant. Based on the limit equilibrium theory of soil, the ultimate bearing capacity of two-layered undrained soil foundation and the failure envelope under horizontal and vertical loading are achieved by using the general-purpose FEM analysis package ABAQUS. In order to cover most problems of practical interest, the ultimate bearing capacity has been computed where H1/B ranges from 0.25 to 3.0, and Su2/Su1 varies from 1 to 6. During the procedure of numerical analysis, the finite element model consists of two clay layers with different thickness and properties, and the finite element mesh uses eight-node modified plane strain rectangular elements to reduce "element locking" and to provide the best solution convergence. The numerical results are compared with Green's theoretical solution, and indicate that the ultimate bearing capacity of two-layered undrained soil foundation depends on the thickness of upper layer soil H1, the undrained shear strength ration of Su2/Su1.