中文摘要：

渗流潜蚀已成为砂土和黏性土双层、多层结构地质条件岸坡崩坍的一个重要成因。潜蚀引起的崩岸属水土相互作用过程，其破坏机理复杂，正确认识各影响因素对工程治理具有重要意义。基于实际岸坡的潜蚀破坏过程，结合渗透破坏理论及锲体分析法主要对堤岸剪切、倾覆两种破坏模式的失稳机理进行分析，表明水位曲线形态、堤岸高度、砂层渗透系数及倾角是影响潜蚀发展状态及堤岸稳定性的关键因素，堤岸背部裂缝充水更增加其不稳定性。由于潜蚀发展的渐进性，水位突降引发的堤岸破坏存在滞后性。

英文摘要：

Seepage erosion has been a major cause of riverbank failure in the geology conditions of sandy and clay soils forming double and multilayer structures. Riverbank collapse caused by seepage erosion is an interaction of water and soil with a complex failure mechanism. A correct understanding of the influence factors is of great significance to engineering management. This paper focuses on analysis and comparison of two major failure modes, i.e. shearing failure and overturning failure, using the theory of seepage failure and wedge stability method and considering the process of actual bank failure. Results show that the erosion development and stability of embankment depend on four key factors： water level variation, embankment height, sand permeability, and the tilt angle of sand layer. Water filling into the cracks on the bank backside greatly enhances bank instability. Due to the progressive feature of erosion development, the bank collapse caused by an abrupt water level drawdown is always delayed.