设置卸荷板的扶壁式挡土墙土压力计算

在扶壁式挡土墙中设置卸荷板可有效地优化结构受力条件，减小直接作用于墙面板上的水平土压力，提高挡土高度，但该类构筑物的结构受力模式复杂，尤其是土压力的计算直接关系到结构计算的可靠度。分别利用朗金土压力和库伦土压力的静力平衡假定条件进行计算分析，指出了朗金公式在计算此类工况土压力时的缺陷，确定了库伦公式的适用性，给出了土压力的具体计算步骤，并提出了适用于库伦公式的卸荷板设计构造要求，为超高扶壁式挡土墙设计提供参考。

Calculation of Soil Pressure for Buttress-type Retaining Wall with Load-off Plate

Setting up a load-off plate in a buttress-type retaining wall can effectively optimize the structural force conditions, reduce the horizontal soil pressure directly acting on the wall panels, and increase the height of the retaining wall. However, the structural force mode of such structures is complex, especially the calculation of soil pressure is directly related to the reliability of structural calculation. The static equilibrium assumptions of Rankine and Coulomb soil pressures are used for calculation and analysis. The defects of the Rankine formula when calculating the soil pressure under such conditions are pointed out. The applicability of the Coulomb formula is determined. The specific calculation steps for soil pressure are given. And the design and construction requirements of load-off plate applicable to the Coulomb formula are proposed, which provides the reference for the design of ultrahigh buttress-type retaining walls.