Mesh-free Limit Analysis of Trapdoor in Cohesive Soils

ABSTRACT:A new numerical approach is developed for examining the stability of purely cohesive layer resting on a trapdoor under plane strain condition. The presented methodis a combination of limit analysis theorems of classical plasticityand, aMesh-free technique. Accordingly, the domain is just simulated by nodes and there is no need of elements in the traditional sense. The limit analysis consists of determining lower and upper bounds and bracketing the true collapse load. In present paper, the Shepardʹs shape functions are used for lower bound analysis due to their special characteristics. In upper bound analysis radial point interpolation shape functions are used. Based on different methods used for discretization, admissible stress and velocity fields are formed respectively, for lower and upper bound analyses. In both approaches, the smoothing technique is used to guarantee the rigorousness of bound solutions. At the end, a computer code has been developed for the limit analysis of trapdoor stability problem and the accuracy and efficiency of proposed method is demonstrated.