不同围护结构变形形式的基坑开挖对邻近建筑物的影响对比分析

当基坑开挖深度相同，而围护结构及支撑系统的差异将使得围护结构将发生不同形式的变形，坑外土体的位移及邻近建筑物的变形也将存在相应差异。针对不同围护结构变形形式对应的基坑邻近建筑物的变形开展精细化分析，算例结果表明：当围护结构发生踢脚、内凸或复合形式的变形时，紧邻基坑的建筑物将发生显著的下凹挠曲变形，且下凹挠曲程度随沉降槽的近基坑侧土体沉降值增大而减小，尤其是当围护结构发生踢脚和内凸变形时，建筑物的下凹挠曲变形最为显著，并产生显著的墙体拉应变，此时邻近的建筑物是最为不利的；而对于任意变形形式的围护结构，当建筑物距基坑距离约为 1 ～ 1.5 倍开挖深度时，均将产生显著的上凸挠曲变形，所引发的建筑物墙体拉应变亦较为显著，即该位置处的建筑物都将是不利的。

Comparative analysis of responses of buildings adjacent to excavations with different deformation modes of retaining walls

For a given excavation depth,the deformation forms of the retaining walls are different owing to various retaining structures and bracing systems.Thus the settlement of the soil and the deformation of the adjacent buildings can be considerably different.The responses of buildings adjacent to excavations with different deformation modes of retaining walls are analyzed.The results show that when the retaining walls exhibit kick-in,convex and composite deformation,for the buildings close to the excavations,sagging deformation occurs and its magnitude depends on the settlement of the soil near the retaining walls.Especially for the kick-in and convex deformation modes of the retaining walls,the sagging deformation is the most significant and the tensile strain on the buildings is severe.In this case,the buildings are in the most adverse situation.For any deformation modes of the retaining walls,when the relative distance between the buildings and the excavations is about(1~1.5) times the excavation depth,the excavations will cause obvious hogging deformation and the tensile strain of the buildings.All the buildings at that location are in most adversity.