条形荷载不同分布模式下挡墙主动土压力研究

针对实际工程中墙后作用有不同分布模式的条形荷载、填土为黏性土,墙背与填土间存在黏着力,采用库仑土压力理论假设,从滑动楔体处于极限平衡状态时力的静力平衡条件出发,推导了适用多种复杂条件下的主动土压力计算式,并给出临界破裂角的显式解答以及各理论计算式适用范围的边界条件。该公式在多段条形荷载作用下可扩展应用,对于不分段条形荷载,只需作相应的简化后便可按相同的方法求解。受边界条件的限制,该公式存在一定的无解区。算例分析结果表明：条形荷载不同分布模式下,相关文献方法提出的主动土压力计算式与该公式的计算结果完全一致；由于未考虑条形荷载对滑动楔体临界破裂解的影响,规范方法得到的主动土压力偏小。

Active earth pressure on retaining wall under different distribution patterns of strip surcharge

With regard to the practical projects with different distribution patterns of strip surcharge on the back of the retaining wall, the cohesive backfill and adhesive force between the soil and the retaining wall, based on the theoretical hypothesis of Coulomb's earth pressure and the static equilibrium of the force when the slide wedge is in limited equilibrium, a formula for the active earth pressure that is suitable for a variety of conditions is deduced. The critical rupture angle of the explicit solutions and the boundary conditions of application scope of each theoretical calculation are also given. This formula can be applied to multistage strip surcharge. For single segment strip surcharge, it can be solved by the same method with the corresponding simplifications. Restricted by the boundary conditions, this formula has a certain domain without solution. The results of example analysis show that under different distribution patterns of strip surcharge, the calculated values by the proposed formula are exactly consistent with those of the relevant literatures. As the influence of the strip surcharge on the critical rupture angle of sliding wedge is not taken into account, the active earth pressure calculated by the approach in the Chinese specifications is small.