复合式重力坝支护结构的两阶段附加弯矩法

Deformation Prediction Method of Composite Gravity Retaining Wall in Two Steps

复合式重力坝基坑支护结构是介于重力式水泥土坝和排桩两种围护形式之间的一种复合支护形式。由于这种复合支护结构内部受力关系复杂,除有限元法外尚未有较好的变形计算方法。在弹性支点法的基础上,提出了一种考虑空间效应的两阶段迭代计算方法。该方法第一阶段按常规弹性支点法计算,第二阶段在第一阶段得到的变形曲线基础上,将内插加筋体摩擦力产生的附加弯矩叠加到围护体的受力与变形计算中。最后结合工程实例的实测结果对该方法进行了对比验证。

Composite gravity retaining wall is one type of excavation support structure that in between gravity retaining wall and piled supporting structure.Since the complicated relationship of this internal structure of the retaining wall,there has not been an appropriate deformation estimation method other than the finite element method.Based on the elastic Winkler model,this paper proposes a two-step iterative calculation method considering its spatial effects.The first step of the calculation is a conventional method in accordance with the Winkler model,the second step is to superpose an additional moment generated by friction of interpolated reinforcement structure to the grid point on the Winkler beam,using the deformation curve obtained by the first step.Through an engineering example,the method is validated.