力矩与水平荷载作用下浅基础破坏包络面方程

为了解决力矩与水平荷载作用下浅基础破坏包络面形状在埋深较大情况下趋于复杂的问题,根据力的平移定理,针对均质和非均质地基上的浅基础,提出了一种搜寻浅基础最优荷载参考点的数值计算方法.基于该方法得到荷载参考点,联合采用swipe加载和固定位移比加载方法进行平面应变有限元分析,得到的二维破坏包络面形状比传统的基于基底中心的包络面趋于对称和简单,给出了浅基础二维破坏包络面的统一数学方程.计算结果表明,该方程能合理描述较大埋深范围内的浅基础在力矩与水平荷载的复合加载情况下的承载性能.

Equation of Failure Envelope for Shallow Foundations Subjected to Moment and Horizontal Loading

To overcome the problem that the shape of failure envelope for shallow foundations with larger embedment to breadth ratio tends to be complex,a numerical procedure to search the optimal load reference point was proposed,according to force translation theorem,for shallow foundations under horizontal and moment combined loading in uniform and inhomogeneous soil.Swipe loading method and fixed displacement ratio loading method were combined to conduct plane strain finite element analysis.The two-dimensional failure envelope based on the optimal load reference point tended to be more symmetric and simple,compared with that based on the center of shallow foundation base.Then,a unified equation was proposed for describing the two-dimensional failure envelope of shallow foundations.Results show that the bearing capacity of shallow foundations subjected to horizontal and moment combined loading is reasonably evaluated utilizing the equation.