根据边坡施工后坡体位移的相对变化趋势，给出了边坡开挖松弛区和预压区的明确定义，将开挖松弛区和预压区统称为坡体影响区，并通过大型模型试验模拟了多级边坡的施工过程，提出了影响区重叠效应的概念。若下级边坡的开挖松弛区（或预压区）与上级边坡的预压区发生重叠，那么会对上级边坡重叠区域的岩土体产生松弛（或加固）作用，从而影响该重叠区域支挡结构的受力情况，重叠范围越大影响越大；对于重叠区范围之外的支挡结构，其受力不受影响，影响区重叠效应是支挡结构受力发生变化的根本原因。

According to the relative variable trend of slope displacement after its construction, this study declared the definitions of the relaxation zone and pre-compression zone, which are collectively referred to as the influenced zone. The construction process of the multi-stage slope was simulated through a large-scale model test. Meanwhile, the concept of the overlapping effect of influence zone was proposed. If the excavation relaxation zones (or pre-compression zones) of lower slope overlapped with pre-compression zones of the upper slope, it would produce relaxation (or reinforcement) effect on the soil and rock of the overlapped zone which belongs to the upper slope. As a result, the force of retaining structure in the overlap zone was influenced. Furthermore, it is found that the wider the overlapped region was, the stronger influence was. However, the overlapping phenomenon had no effect on retaining structures outside the overlapped region. Therefore, the reason for the force change of retaining structure was essentially caused by the overlapping effect in the influenced zone.