Model test study on landslide of reservoir bank near dam under antecedent rainfall

摘要

Based on the rainfall profile in the area of the reservoir bank near the dam of Longjiang hydropower plant in Yunnan Province, the authors investigate the landslide under antecedent rainfall. By using the self-developed experimental apparatus, a model test which simulate the landslide under antecedent rainfall in laboratory have been conducted and the characteristics of the landslide under the antecedent rainfall have been investigated. The research shows that the antecedent rainfall is a major factor of the landslide. The antecedent rainfall infiltrates into the slope from the slope surface which reduces the soil strength so that the rainfall in the later time could easily initiate the landslide. The loss of or reduction of suction in the slope caused by the antecedent rainfall, which is the major reason for the landslide, and this kind of landslide is categorized into shallow retrogressive landslide.