【摘要】 在渗流固结耦合理论的基础上,应用通用有限元软件ABAQUS建立开挖与降水开挖的三维基坑模型。通过对比分析,总结了基坑开挖降水过程中基坑坑底隆起的基本规律,分析了软土地区深基坑坑底隆起变形及其影响因素。得出工程降水对深基坑土体的压密作用以及基坑隆起最大位置向基坑地下连续墙移动的现象,得到降水对基坑稳定有利的结论。同时进行经验公式计算结果与有限元模拟结果的对比,得出有限元结果的可参考性。更多还原

【Abstract】 Based on the theoretical analysis of coupling seepage with consolidation,two pit models were established by use of the general commercial software ABAQUS.One was based on the total stress theory without considering the role of water,the other was based on the effective stress theory considering the fluid-solid interaction effect due to dewatering and excavation. The differences between the finite element analysis results were compared,and the basic disciplines of bottom rebound were summarized.The influencing factors of bottom rebound due to deep excavation in soft soil area were analyzed.The conclusion is that soil is compacted during dewatering and the position of the largest bottom rebound moves to the concrete diaphragm walls due to excavation and dewatering.From the above analysis,dewatering is beneficial to the stability of the foundation pits. At the same time,the results of empirical formula were compared with those of FE analysis,indicating that the results of FEM analysis are referable.更多还原