large deformation modeling of trapdoor test using mls-mpm

Moving least squares material point method (mls-mpm) is a new method to allow for sharp separation of particles and to reduce the cell-crossing error in the material point method simulations. this paper uses mls-mpm method to numerically simulate the trapdoor test and soil arching, a phenomenon which plays a vital role in the design of many geotechnical structures, such as pile-supported embankments, buried pipelines, tunnels, and trench excavations. large deformation of soil is considered during the plastic phase of deformation. non-associated mohr-coulomb plasticity is enhanced to capture strain hardening/softening typically seen in granular soils. the proposed method is validated against centrifuge trapdoor tests. the numerical stress fields agree with the formation of triangular shaped arch after medium relative displacements and mobilization of a prism of soil after large relative displacements of the trapdoor. it is shown that using mls-mpm, the arching behavior of soil can be described in detail throughout the trapdoor test.