Failure Behavior and Mechanism of a Slope Under the Action of Earthquake and Rainfall

Earthquake and rainfall may be coupled, which will lead to landslides easily, but the studies about this problem are at the initial stage. In this paper, the failure behavior and mechanism of a slope under the action of earthquake after rainfall were investigated with a shaking table test, based on similarity law. The experimental results showed that the failure process of the slope during earthquake after rainfall undergoes four characteristic stages. There exist velocity zoning in the slope during failure. The moisture content of soil in the slope has different growth rates at different positions during rainfall. Transient and cumulative pore water pressure occurs in the slope during earthquake after rainfall. However, due to the short period of earthquake action, the soil moisture content is not very sensitive to this action, but the pore water pressure changes sharply during earthquake. Under the combined action of rainfall and earthquake, there is a multi-physical field effect in the slope. Rainfall weakens the strength of the soil, mainly causes local instability of the slope. More extensive damage of the slope is caused under the combined action of seismic inertia force.