软岩隧道施工变形修复方案优化研究

某隧道在建设过程中,由于上覆荷载大,围岩强度较低,围岩出现了较大变形,严重影响隧道安全,需对隧道进行修复.根据实际情况设计了反增加初期支护厚度和增加初期支护厚度并加固围岩2种修复方案,并依据实测地形分别建立了有限元计算模型,采用不同的工况模拟了隧道修复方案.对计算结果从围岩位移、应力、塑性区发展以及衬砌内力等方面进行了对比和分析.研究结果表明,围岩注浆对软岩隧道的围岩变形、围岩应力的控制效果优于仅采用增加初衬厚度的修复方案.此研究对类似隧道修复具有借鉴意义.

Study on Reparation Designs Optimization of Tunnelling in Soft Surrounding Rock

Due to overload from covering rock and low strength of surrounding rock,severe deformation of first lining are found during tunneling in an area composed of soft rock,which threatens the safety of the tunnel.Two kinds of reparations designs of the tunnel is studied by FEM computation.The FEM models are built according to actual topography of the tunnel.Different load cases are set up to simulate the procedure of the construction.Results of displacement,stress and plastic zone in rock and inner forces in fir...