深基坑土钉支护的弹塑性数值模拟

ELASTO-PLASTIC NUMERICAL SIMULATION OF SOIL NAILING SUPPORT OF DEEP FOUNDATION PIT

深基坑工程是一类典型的变体系施工力学问题,并且常常涉及土体物理非线性和土与支护结构的接触非线性这类双重非线性问题。首先,阐述了基坑工程这类变体系施工力学问题所具有的特点;然后,给出了同时考虑开挖与支护过程以及双重非线性问题的有限元计算方法;最后,通过对某一土钉支护的基坑算例进行数值分析,研究了土钉内部拉应力和钉–土界面上的剪应力分布模式以及开挖过程对这两种应力的影响。计算结果比较理想,从而进一步证明了所发展的计算方法的正确性。

The stresses and deformations of soils and support structures of foundation pit will change continuously during the course of excavation and supporting. The physical non-linearity of soils and the contact non-linearity of interface between soils and support structures often form the double nonlinear question 6f civil engineering structures. The mechanical characteristics of foundation engineering are represented based on the detailed description of support system. Then the finite element method and the nonlinear iterative method are presented considering the process of excavation and supporting and the double non-linearity problem. Finally, an illustrative example is analyzed numerically, the relationship between the distribution mode of tension stresses of soil nailing and shear stresses of nailing-soil interface, and the excavation steps are studied. Computational results show that the presented method is rational.