深基坑复合支护技术三维数值模拟研究

北京市某深基坑工程深19.7 m,采用土钉墙与桩锚相结合的复合支护技术,取得了很好的支护效果。采用有限差分法对该工程的典型支护形式开展了三维数值模拟研究,得出了在分步开挖过程中,土钉墙支护中土钉的工作方式和受力历程,以及桩锚支护中护坡桩与锚杆之间的受力协调过程,并与基坑边坡位移及支护体受力的实测数据进行了对比分析,为深基坑复合支护技术的发展和设计提供科学的指导依据。

3D Numerical Simulation Study on Composite Supporting Technology of Deep Foundation Pit

The composite supporting technology combining the soil-nailing wall with pile-anchor system was used in a deep foundation pit supporting engineering with excavation depth of 19.7 m in Beijing,and the supporting effect is very good.The typical supporting form was studied by the method of three-dimensional numerical simulation with finite difference,and the result showed the work mode and force mechanism of the soil-nailing wall and force coordination process of slope protection pile and anchor bolt in pile-anchor retaining.Comparative analysis was made on the measured data of foundation pit slope displacement and retaining structure force,which can provide scientific guidance to the development and design of the deep foundation pit composite supporting technology.