深基高填明洞的受力分析

Analysis on Mechanical Behaviors of Open-cut Tunnel with High Fill and Deep Foundation

深基高填明洞较普通明洞受力更复杂,设计需要考虑更多的因素,如结构的内力、变形、整体和局部稳定等。文章主要采用数值计算法分析了坝基础、衬砌、填土在不同施工步骤中的稳定性、内力和变形,采用结构力学法分析了外衬砌的内力。分析结果表明坝和明洞在施工阶段和运营阶段能保证整体稳定,内衬砌应在I期填土后施作,采用结构力学法计算的弯矩值大于数值计算的结果。

The mechanical behavior of open-cut tunnel with high fill and deep foundation, compared with that of a common open-cut tunnel, is featured with more complexity, thus has to ponder on such factors in design as the internal force of the structure, deformation, the entire or partial stability. In this paper, numerical method is employed to analyze the stability, internal force and deformation of the dam foundation, lining, filling in different construction procedures, and method of structural mechanism is employed to analyze lining internal force. The result indicates that entire stability of dam and open-cut tunnel can be ensured at construction stage and operation stage, the internal lining should be constrncted following completion of first filling. The bending moment value calculated by method of structural mechanics shall be larger than that calculated by numerical value.