盾构衬砌环开裂后的应力与变形分析

结合运营盾构隧道实例,建立了衬砌环开裂后三维非线性有限元计算模型;结构计算模型采用实体单元,衬砌结构裂缝及接头作用分别用古德曼(Goodman)单元及组合弹簧模拟,应用有限元程序GTS分析荷载作用下带裂缝衬砌结构的应力与变形情况,且与衬砌结构不考虑裂缝影响力学性能进行了对比,最后用实测数据验证了数值分析结果。结果表明:考虑衬砌环带裂缝模型可以有效地分析结构的应力和变形性质,可作为衬砌结构开裂后力学性能分析手段;衬砌结构开裂后对结构受力与变形影响较小,主要集中在裂缝周围小区域内,即对承载力影响较小,主要考虑对耐久性的影响。

Analysis on Stress and Strain of Shield Tunnel Lining Structure with Cracks

With example of operating shield tunnel, a three-dimensional nonlinear Finite Element Method model for lining with cracks is set up. Three-dimensional solid elements are adopted to simulate the structure and using Goodman unit and combination spring to simulate the crack and joint. The stress and deformation of lining structure with crack are discussed by Finite Element Method model code Geotechnical and Tunnel analysis System, comparing it with model that not considering the influences of structural cracks. And then, the results of numerical analysis are verified by measured data. The results of the study show that three-dimensional Element Method model can effectively analyze the stress and deformation of structure with cracks and can be used as the analysis method of mechanical properties of lining structure with cracks. The cracks have little influence on the stress and deformation of structure, that is to say less influence on bearing capacity, the main influence is on durability.