有荷载作用时挡土墙主动土压力的计算

在工程中计算挡土墙的主动土压力,朗肯土压力理论和库仑土压力理论因其简单实用仍得到较多的应用,但两者却存在着一定的局限性,即对于实际工程很难严格满足其假设条件。基于库仑理论的平面滑裂面假定,考虑滑裂面上填土的粘聚力及填土与墙背接触面上的粘着力等因素的影响,分析了有荷载作用时滑动土楔体的极限平衡状态,并利用力矢多边形推导出了有荷载作用时主动土压力（粘性土、无粘性土）的计算公式。分析表明：提出的对粘性土主动土压力计算方法,可以不受传统朗肯理论和库仑理论较为苛刻的假设条件的限制,具有普遍的适用性。

Computation of Active Earth Pressure of Retaining Wall under Uniform Surcharge

In the calculation of active earth pressure for retaining walls, Rankine earth pressure theory and Coulomb earth pressure theory still receive more applications. Because they are relatively simple and practical, but there are certain some limitations. For example, it is very difficult to meet their stringent assumptions in real projects. Based on sliding plane hypothesis in Cou- lumb earth pressure theory, this paper studies the cohesion forces on sliding surface and the adhesive force on interface of retaining wall. For a problem with loads acting on at the sliding wedge, balance of the limit is analyzed, and the formulas for active earth pressure are derived by use of the vector polygon. Analytical results show that the method of calculating active earth pressure can be exempted from the traditional Coulomb Rankine theory on the assumption which is more stringent restrictions. The method in this paper could be widely used.