复杂应力条件下不同锚杆支护的巷道稳定性

以金川集团三矿区1 110 m分段掘进巷道为工程背景，为解决巷道破坏严重、返修率高的难题，采用FLAC^3D数值模拟软件，对涨壳式中空预应力锚杆和全长砂浆锚杆的支护效果进行了数值分析，比较了2种锚杆支护在最大水平主应力与巷道轴线呈不同夹角或相同夹角、最大水平主应力大小不同等条件下的巷道变形、围岩应力场、塑性区以及应力集中系数的差异。通过与现场试验数据进行对比，发现采用涨壳式中空预应力锚杆支护的巷道，在控制巷道两帮位移方面，其效果要好于全长砂浆锚杆支护的巷道；采用了涨壳式预应力锚杆支护的巷道周边受力更加均衡，有利于巷道的长期稳定，能延长巷道的维修周期，降低巷道返修率。

Stability comparison of the roadway supporting by different types of anchor under complicated stress conditions in Jinchuan No.3 mine area

With 1 110 m sublevel drift of Jinchuan No.3 Mine Area as engineering background，and in order to solve the issues of serious roadway damage and higher repair rate，the numerical analysis on the supporting effect of expanding-shell hollow pre-stressed anchor and full-length mortar anchor were conducted by FLAC3D numerical simulation software.The differences of roadway deformation，surrounding stress field，plastic zone and stress concentration factor in two conditions are contrasted:one was the different angle between the maximum horizontal principal stress and roadway axis of the two bolt supports，the other was the different maximum horizontal principal stress with the same angle.And compared with the field test data，it was found that the effect for controlling the two sides’ displacement of the roadway supported by expanding-shell hollow pre-stressed anchor is much better than mortar bolt.Besides，the tress in the roadway periphery which supported by expanding-shell hollow pre-stressed anchor is more balanced，which contributes to the long-term stability of the roadway and can prolong the roadway maintenance cycle and reduce the repair rate.