墙体绕基础转动情况下挡土墙主动土压力分布

采用库仑土压力理论的假设 ,挡土墙上的主动土压力是由墙后填土在极限平衡状态下出现的滑动楔体产生 ,在该滑动楔体上沿填土深度方向取水平层薄单元进行分析 ,建立关于挡土墙上土压力强度的一阶微分方程 ,给出了墙体绕地基转动变位模式下 ,土压力强度、土压力合力和土压力合力作用点的理论公式 ,并与库仑土压力理论、墙体平动变位模式下土压力和有关实验结果进行了比较分析。结果表明 ,墙体绕地基转动变位模式下土压力合力与墙体平动变位模式下土压力合力相等 ,并等于库仑土压力理论计算结果 ,但土压力合力作用点和土压力分布有显著差别。

Distribution of active earth pressure with wall movement of rotation about base

Based on the Coulomb’s concept that the earth pressure against the back of a retaining wall is a thrust exerted by the sliding soil wedge formed by the back of the wall and a plane passing through the bottom edge of the wall with an the angle of inclination θ.The differential equation of first order is set up by the equilibrium of forces on the slice taken out from the wedge. The theoretical answers to the unit earth pressures, the resultant earth pressures and the points of application of the resultant earth pressures on retaining wall are obtained for the wall movement mode of rotation about base. The comparisons are made among the formula presented here, the formula for the wall movement mode of translation, the Coulomb’s formula and some experimental observations. It is demonstrated that the magnitudes of the resultant earth pressures for the wall movement mode of rotation about base is equal to that determined by the formula for the wall movement mode of translation and the Coulomb’s theory, but the distribution of the earth pressure and the points of application of the resultant earth pressures are significantly different.