基于混凝土塑性损伤模型,建立了透水型拦挡坝三维数值计算模型,根据单因素理论,通过数值计算,揭示了拦挡坝排泄孔及坝趾附近最大拉应力及Mises等效应力随排泄孔高宽比、开孔数量、开孔率及开孔位置的变化规律;并对排泄孔不同开孔率条件下拦挡坝承受的极限冲击荷栽进行了研究。结果表明:①最大拉应力随高宽比增大先减小后增大,随开孔率及开孔数目的增大基本保持不变,随垂直距离的增大而减小。Mises等效应力随高宽比的增大先减小后增大,随垂直距离的增大而减小,随着开孔率的增大而增大,随开孔数目的增大基本保持不变;②开孔会降低坝体抗拉强度且随着开孔率的提高,拦挡坝坝体承受的泥石流冲击力最大值呈降低趋势。该研究成果可为透水型拦挡坝结构设计与优化提供理论指导。

Based on concrete plastic-damage model, a three-dimensional numerical calculation model of permeable dam is established. According to the theory of single factor, the chang rules with the depth-width ratio, number, opening ratio and position of drain holes for the maximum tensile stress and Mises equivalent stress near the permeable dam drain hole and dam toe are revealed through numerical simulation. Finally, how to withstand the ultimate impacting load for a permeable dam is studied. The results show that the maximum tensile stress decreases firstly, and then increases with the increasing of depth-width ratio, remains little changing with the increasing of opening ratio and number of holes and decreases with the increasing of vertical distance; Mises equivalent stress decreases firstly, and then increases with the increasing of depth-width ratio, decreases with the increasing of vertical distance, increases with the increasing of o-pening ratio, and remains little changing with the increasing of the number of holes; drain hole reduces the tensile strength of the permeable dam and with the increasing of opening ratio,the maximum impact force of debris flow on the permeable dam will reduce. Research results can provide a theoretical guidance on structural design and optimization for permeable dams.