破碎矿岩巷道分区支护设计与力学分析

Design and Mechanical Analysis for Broken Tunnels Separation Support

"湿喷混凝土+树脂锚杆"支护技术以其良好的应用效果,在井巷工程中得到了广泛应用。针对某矿山矿石围岩破碎、支护难度大的问题,应用喷射混凝土作用机理、喷射混凝土强度与围岩稳定性的力学关系等原理,结合矿山的工程地质现状,对巷道支护方案进行了设计。对于喷层厚度的计算分别应用了冲切破坏理论、黏结破坏理论、剪切破坏理论以及锚杆间荷载原理,最终得出在巷道顶板的混凝土喷层厚度不应小于54mm,巷道两帮的混凝土喷层厚度不应小于15mm。应用组合梁理论对树脂锚杆参数进行分析,结果表明锚杆长度要大于2.56m,间距小于1.53m。根据计算结果进行了巷道支护的现场应用,取得了较好的效果。

Combined wet shotcrete and resin bolt support technology has been widely used in underground mining with good performance. Mining support is usually a big challenge for crushed orebody. In this paper,a supporting design for broken tunnels based on the mine geology was brought out;where theories,such as the relation between shotconcrete strength and surrounding rock stability,mechanism of shotconcrete action,were involved. Spray layer thickness was calculated according to principles of punching failure,bonding failure shear failure,and the load between the bolts theory as well. The result indicated that the thickness of shotcrete should be no less than 54 mm on the roadway roof and no less than 15 mm on the two sides of the roadway. The mechanical behavior for resin bolt was analyzed in the light of composite beam theory,which suggested the bolt length should be greater than 2.56 m and the spacing less than 1.53 m. According to the calculation results,the field application of roadway support was carried out,and good results were obtained.