基坑围护墙体变形多因素影响研究

Study on the Multi⁃factor Influence of Foundation Excavation Retaining Wall Deformation

根据弹性地基梁张有龄法,建立了基坑围护墙体的扰曲微分方程,求得了其解析解,表示出墙体侧向位移与开挖深度、墙体插入深度及墙体厚度的数学关系式,进而通过算例分析了不同插入比与墙体厚度对墙体侧向位移的影响。研究结果表明:在一定开挖深度内插入比为1~1.4比较经济合理,墙体水平位移在此后开始骤增,如继续开挖应加设横撑、斜撑等支撑结构,以保证基坑安全;墙体厚度取1~1.5m比较经济合理。研究结果与FLAC3D模拟结果一致,并成功应用于实际基坑支护工程中。

Based on the elastic foundation supported beam method,the perturbation differential equation of the wall of the foundation excavation is established.Its analytical solution,which shows the mathematical relationship between the lateral displacement of the wall and the excavation depth,the wall insertion depth and the wall thickness,is obtained.Then,the effects of different insertion ratios and wall thicknesses on the lateral displacement of the wall are analyzed through examples.Research results show that an insert ratio of 1~1.4 is more economical and reasonable within a certain excavation depth,and the horizontal displacement of the wall begins to increase sharply thereafter.If excavation is to be continued,support structures,such as horizontal braces and diagonal braces,should be added to ensure the safety of the foundation excavation,and a wall thickness of 1~1.5m,which is economical and reasonable,should be adopted.Research results are consistent with those of FLAC3D simulation,and have been successfully applied to the actual foundation excavation support project.