考虑实际地层分布软土深基坑施工过程力学行为研究

以典型工程为依托,运用surfer软件形成实际地层,借助有限元软件建立精细的计算模型,计算分析了软土深基坑开挖、支护及拆撑全过程围护结构和地表变形情况,并通过现场实测验证。研究结果表明:①软土深基坑开挖支护连续墙最大侧移Δh变化范围为(0.01%~0.08%)h;②开挖完地表最大沉降Δv为(0.03%~0.04%)h,出现在墙外0.56h位置并满足(0.38~0.57)Δh;③地下结构施作拆撑对基坑变形产生了明显的影响,拆撑使长、短边围护墙位移较开挖完分别增加16.0%和14.2%。

Research on Mechanical Behavior of Soft Soil Deep Foundation Pit Construction Process Considering Actual Stratigraphic Distribution

Based on typical engineering example, the actual landform was formed by surfer software and then the refined calculation model was established by finite element software. The building envelope structure and surface deformation in the soft soil deep foundation excavation, support and dismantling and supporting process were calculated and analyzed, and on-site measurement and verification were done. The results showed that ① the maximum lateral displacement Δh is (0.01 %~0.08 %) h after foundation excavation and supporting of soft soil deep foundation pit. ② After excavation, the maximum settlement Δv is (0.03 %~0.04 %) h, which presents to 0.56 h outside the wall and satisfies (0.38~0.57)Δh . ③The influence of dismantling and supporting on foundation deformation was significant. The displacement increments of enclosure structure increase respectively by 16.0 % and 14.2 % in long and short side, so it should be fully considered in the research of mechanical characteristic of foundation pit construction.