The effects of backfill cohesion on the seismic behavior of a retaining wall are discussed on the basis of a series of 1 g shaking table model tests. The model test results show that a retaining wall having cohesive backfill soil is more stable than a wall without it. The following aspects are observed in the cases of cohesive backfill soil from a detailed analysis using the measured seismic active earth pressure acting on the retaining wall: 1) the existence of a stable region at the top part of the backfill soil, 2) the increase in shear force acting on the boundary between the back face of the wall and the backfill soil, and 3) the mobilization of cohesion along the failure plane in the backfill soil.

The existence of a stable region results in reductions in both the driving force and the overturning moment, while it tends to disappear under a high seismic load. The increase in shear force acting on the back face of the wall contributes to an increase in the resistant moment against the overturning of the wall with respect to the base of the footing, and it mobilizes even under a high seismic load. Mobilized cohesion along the failure plane contributes to the support of the soil wedge, resulting in a decrease in the seismic active earth pressure. It also continuously mobilizes even under a high seismic load.

These observations indicate that giving consideration to the backfill cohesion when calculating the seismic active earth pressure leads to the rationalization of the evaluation of the seismic performance of the retaining wall even though further study is required, namely, carrying out the validation in the prototype scale and setting the applicable conditions for the seismic design.

在一系列 1 g 振动台模型试验的基础上讨论了回填土内聚力对挡土墙抗震性能的影响。模型试验结果表明，具有粘性回填土的挡土墙比没有它的墙更稳定。使用测量的作用在挡土墙上的地震活动土压力进行详细分析，在粘性回填土的情况下观察到以下几个方面：1）回填土顶部存在稳定区域，2）增加作用在墙背面和回填土之间边界上的剪切力，以及 3) 沿回填土中的破坏平面的凝聚力的动员。

稳定区的存在导致驱动力和倾覆力矩均减小，而在高地震载荷下趋于消失。作用在墙背面的剪力的增加有助于增加抵抗墙相对于基础基础的倾覆的抵抗力矩，即使在高地震荷载下它也能移动。沿破坏面的动员黏聚力有助于支撑土楔，从而降低地震活动土压力。即使在高地震载荷下，它也能持续移动。

这些观察结果表明，在计算地震活动土压力时考虑回填土的粘聚力可以使挡土墙抗震性能评估的合理化，即使需要进一步研究，即在原型规模上进行验证和设定抗震设计的适用条件。