结合大量现场实测数据,系统分析了基坑开挖过程中维护结构变形、地表沉降以及周围建筑物的变形规律,监测结果显示:维护墙体变形整体呈“纺锤”状,并具有明显的时空效应,随着开挖深度的不断加深,地下连续墙水平位移的最大值也不断向下移动;地表沉降曲线表现出明显的“沉降盆”,在距离基坑边缘一定距离处达到最大值,并随着距基坑距离的不断增大,地表沉降逐渐减小,且深层土体的开挖对地表沉降的影响尤为明显;加强邻近历史建筑物侧的基坑维护和防水措施以及对历史建筑物地基的加固处理有效地控制了历史建筑物沉降。结论对在密集建筑群中软土地基上基坑设计和开挖具有一定的实用价值和借鉴意义。
Based on a large amount of experimental data,the rules was analyzed about the structure deformation,ground settlement and surrounding building deformation during excavation process.The monitoring results show that the deformation of the maintenance wall presents“spindles”shape,and has a space-time effect.With the increase of excavation depth,the maximum lateral displacement of diaphragm wall is constantly moving downward;surface subsidence curves show a “settling basin”,which means the subsidence reaches a maximum at a certain distance away from foundation pit edges,and the surface settlement gradually decreases as the distance increases, and the impact on surface subsidence in excavating deep soil is obvious;the settlement of the historical buildings can be controlled by reinforcing the lateral foundation enclosure and waterproof measures before excavating,as well as by the reinforcement of the historical building foundation. The conclusions provide some practical value and valuable reference for designing and excavating the soft soil foundation under crowded buildings.