浅埋偏压隧道开挖数值模拟及稳定性研究

浅埋偏压会对隧道围岩稳定和支护结构产生很大影响,开挖过程中极易发生垮塌。利用FLAC3D 程序对烟海高速公路解家河隧道穿越浅埋偏压洞段采用的施工过程进行仿真分析,得到解家河隧道在采用不同开挖工序时各阶段围岩及支护结构的变形和应力变化情况。结合现场监测断面的量测成果,经过数据整理和计算得到解家河隧道浅埋偏压洞段围岩及支护的受力特征,对隧道围岩稳定性进行分析判断。所得结论为解家河隧道顺利施工提供了可靠依据,可为具有类似地质、地形情况的隧道设计和施工提供技术参考。

Study on numerical simulation and stability analysis shallow buried tunnel excavation under unsymmetrical pressure

Shallow buried and unsymmetrical loaded section of tunnel have a great impact on surrounding rock stability and ground support structure, which could lead to the happening of collapses in tunnel excavation at these sections. The method of FLAC3D was employed to conduct numerical analysis of construction process on shallow buried and unsymmetrical loaded Xiejiahe section in Yanhai expressway. Thus, the deformation and stress variation condition of surrounding rock and supporting structure on Xiejiahe tunnel were gained under different excavation procedures. Based on measurement result of cross-sections from field monitoring, the mechanic characteristics of surrounding rock and supporting structure on shallow buried and unsymmetrical loaded Xiejiahe section were gained by data collection and calculation to analyze the surrounding rock stability. The conclusion could provide a reliable method for the successful construction of Xiejiahe tunnel, which could also afford technical reference for tunnel design and construction of similar geological situation.