Investigation of the effect of cyclic loading on the soil arching using damped spring-based trapdoor model

Abstract

Cyclic loading greatly affects soil arching, and existing studies mainly investigate the effect of cyclic loading on soil arching by a fixed rigid trapdoor model, failing to simulate the flexible energy-absorption and interaction between fill and soft soil under cyclic loading. A numerical model of the damped multi-segment spring-based trapdoor is established to investigate the development of the soil arching under cyclic loading in terms of the macro and micro dynamic responses by varying the spring stiffness, the relative density of the fill and the fill height. Compared to the traditional fixed trapdoor, the damped spring-based trapdoor can reduce the reflection of the dynamic wave and the weakening effect of the cyclic loading on the soil arching in the initial loading stage; the rebounded spring-based trapdoor in the post-loading stage, however, causes a negative soil arching and prolongs the periodical oscillation of the trapdoor to magnify the weakening effect of cyclic loading on the soil arching. In addition, the increase in the compactness of the fill increases the effect of the cyclic loading on the soil arching, while the increase in the fill height can effectively reduce the effect of the cyclic loading on the soil arching.