山岭隧道突水对衬砌结构受力影响数值分析

Numerical Analysis of the Suddenly Effluent Water Influence on the Mechanical Behavior of the Lining Structure in Mountain Tunnel

用有限元数值模型,分析隧道断面上8个不同位置10种不同水压突水条件下衬砌结构的受力特征。结果表明:突水位置发生在仰拱或墙脚位置时,对衬砌结构的受力影响显著;突水对衬砌结构上的最大正弯矩和最大剪力影响最显著,而对最大负弯矩和最大轴力影响要相对小一些。运用结构力学的弯矩影响线理论,把突水压力作为衬砌结构上的移动荷载,给出不同突水压力下衬砌结构的弯矩包络图。

Mechanical behavior of lining structure is analyzed under 10 different conditions that high water pressure suddenly effluent water upon 8 different parts of tunnel section with FEM numerical model. The results show that mechanical behavior of lining structure changes evidently when suddenly effluent water happens at inverted arch or foot of wall. Suddenly effluent water influences most evidently on maximum of positive bending moment and shear force of lining structure but influences smaller on maximum of negative bending moment and axial force. Figures of all-embracing moment of lining structure on different water pressure are given, taking pressure of suddenly effluent water as move load act on lining by applying the theory of structure mechanics moment influence line.