Investigating the origin of the soil arch in the trapdoor problem: Photoelastic measurement and discrete element simulation

Abstract

Soil arching in the trapdoor problem was investigated via the physical model test and the discrete element simulation. Under the relatively low confining pressure in the physical test, it was found that the sequential transition of the vertical pressure from the trapdoor at the center to contiguous locations in a progressive manner. Uniformity of the particle size distribution in the physical test attributes unsuccessful generation of the resisting internal structure against the generation of the failure surface along which the particles lost their contacts. In the discrete element simulation using polydisperse spherical particles, high values of coordination number and confining pressure can develop the strong internal structure resisting the progressive collapse of the particle assembly caused by the trapdoor movement.