隧道仰拱初期支护钢架缺失整治技术
Remediation technology about the lack of steel frame of tunnel primary support on the inverted arch

新建兰渝铁路某隧道仰拱初期支护钢架缺失,运用有限元软件ANSYS采用荷载-结构模型计算隧道断面各处内力。按破损阶段法求出隧道断面各位置的安全系数,得出拱顶位置的安全系数最小,且不满足规范要求,需采取整治措施。根据计算结果提出一种整治措施,即采用中空注浆锚杆对仰拱进行注浆补强,该方案改善了隧道仰拱周边围岩的力学性能,也使仰拱初期支护恢复力学效应,取得了良好的整治效果。该技术对类似的隧道病害整治有一定的参考意义和推广价值。
Due to the lack of steel frame of primary support on the inverted arch of a tunnel on new Lanzhou-Chongqing railway, the load-structure model isused to calculate the internal force of tunnel cross-section with the finite element software ANSYS. According to the broken phase method, the safety factor of tunnel cross-section of each position is calculated. The result shows the safety factor of vault location is minimum, and it did not meet the requirements of code. There is a need of taking some measures. According to the calculation results, a regulation measure is brought forward. This method can be concluded as: grouting the inverted arch by hollow grouting bolt to reinforce it. By this way, the mechanical property of surrounding rock near the inverted arch can be improved, the mechanical effect of primary support on the inverted arch ianbe been restored, and it has achieved good effects. This technology has some reference significance and promotion value to the similar tunnel diseases