软岩大变形巷道支护技术及应用

Support technology and its application for large deformation of soft rock roadway

针对三门峡铝土矿软岩巷道大变形难支护的问题,综合现场工程地质调查、软岩水理作用测试、现场测试等手段和方法,对该地区巷道破坏模式和失稳机理进行详细分析,提出了锚喷-砌碹相结合的互补支护技术。按照互补支护参数建立数值模型并进行稳定性分析,数值计算结果表明在此支护方式下巷道各部位围岩收敛变形控制良好,且支护后围岩安全系数较之前明显提高。将新支护方案进行工程试验,巷道变形监测数据表明,支护后的巷道变形得到了良好的控制,混凝土喷层未出现裂缝,围岩变形速度迅速减小;锚喷10天后围岩变形基本稳定,此时进行二次砌碹支护效果最好,可以保证巷道的长期稳定。

Aiming at the difficulty of supporting soft rock roadway with large deformation in Sanmenxia bauxite mine, the failure mode and mechanism of roadways in the area were analyzed using field geological survey , test of interaction between water and soft rock , field test and other methods in detail .The combined supporting scheme of spray-anchor and masonry-lining was proposed as well .According to the parameters of this supporting scheme , the numerical model was established and its stability was calculated .The numerical computing results showed that the convergence deformation of surrounding rock in roadway , which employed such supporting scheme , was controlled well, and the safety factor of roadway after supporting increased .By conducting engineering tests with the new sup-porting method , it showed that the deformation of roadway after supporting was controlled well , the crack did not come out in concrete spray layers and the deformation velocity decreased rapidly based on deformation monitoring data.It also showed that the deformation of surrounding rock in roadway was controlled basically after spray -anchor supported for ten days .It was the best time for performing the secondary spray-anchor supporting , which was able to ensure the long-term stability of roadway .