Effective rainfall amount and slope surface failure caused by heavy precipitation

摘要

We reveal the relationship between the occurrence of shallow landslides triggered by heavy rainfall and the amount of effective rainfall using an equation involving the saturated seepage flow. The relational expression of the saturated seepage flow is expressed by an equation of continuity considering the amount of rainwater that infiltrates the soil layer, bedrock and the amount of water drained from the bedrock. Based on a tank model analysis, the amount of pore water included in the seepage flow within the soil is used to explain the amount of effective rainfall (D ) and to obtain the previously mentioned effective rainfall equation. The coefficient of the amount of effective rainfall is linear to regional precipitation, which is unique to every region.