渔寮隧道围岩内部位移与支护结构受力分析

Analysis on Internal Deformation and Supporting Structure of Surrounding Rock in Yuliao Tunnel

基于风化节理岩层中渔寮隧道的实测围岩应力,围岩变形以及支护结构受力等数据,结合解析公式计算以及数值模拟的结果,从围岩松动圈半径,支护结构变形与受力评价了围岩稳定性与支护效果。结果表明:渔寮隧道出口段围岩条件较好,最大围岩内部变形达7.71mm,推测拱顶松动围圈岩厚度半径达3.1m,拱腰、拱肩处松动圈围岩厚度大于4.0m,锚杆轴力的分析反映出围岩松动范围内的锚杆受力较大;支护结构受力特征分析表明因隧道拱顶、仰拱处围岩变形较大而传递给支护结构的附加荷载导致其受力增加;数值计算结果显示不同工序打设的锚杆变形存在明显区别。基于围岩变形规律与支护结构受力分析结果,提出了相应的施工措施与支护结构优化意见。

Based on the measured surrounding rock stress,deformation and support structure stress in the weathered rock formation,combined with analytical formula calculation and numerical simulation,from the aspects of surrounding rock loose circle radius,support structure deformation and force,this paper evaluated surrounding rock stability and support effect.The results showed that the surrounding rock conditions of the exit section of the Yuliao tunnel were better,the maximum deformation was 7.71 mm,and the thickness of the loose roof of the arch was 3.1 m.The thickness of the loose circle at the arch waist and the arch shoulder was more than 4.0 m.The analysis reflects that the bolts in the loose area of the surrounding rock are subjected to large forces.The stress characteristics of the supporting structure indicate that the additional load transmitted to the supporting structure due to the large deformation of the surrounding rock at the vault and the arch causes the force increase.The numerical calculation results show that there is a significant difference in the deformation of the bolts installed in different processes.Based on the deformation law and the force analysis results of supporting structure,the construction measures and support structure optimization suggestions are proposed.