考虑接触影响的超深嵌岩地下连续墙支护深基坑开挖模拟

本文用Drucker-Prager模型和基于直接约束的接触算法模拟了超深嵌岩地下连续墙支护深基坑开挖全过程。模拟结果表明设置接触后计算结果更接近工程实测值，明显优于不设置接触情况；墙体嵌岩部分拉应力和压应力都很大；开挖至一定深度后，支护结构受力和变形变化不明显；考虑混凝土开裂和钢筋的加强作用对变形计算结果影响不大。所得出的结论为嵌岩基坑支护结构设计优化和施工控制提供了理论依据和实践参考。

Excavation Simulation of Super Deep Foundation Pit Braced by Rock-Socketed Diaphragm Wall Considering Contact Effect

All thirteen excavation stages of a super deep foundation pit braced by rock-socketed diaphragm wall are simulated in this article using Drucker-Prager soil model and contact algorithm based on direct control method. FEM simulation results reveal that both tensional and compressive stress are very large at wall foot which is socketed into rock. Results also indicate that after having reached a certain depth,wall displacement and ground settlement change very little due to further excavation. Considering crack of concrete and reinforcing of rebar has little effect on calculated wall displacement and soil settlement. These conclusions provide theoretical basis and practical references for design optimization and construction control of such kind of deep pit.