Jinchuan nickel mine is the largest underground metal mine in China,There is highly stressed weak rockmass in this mine. The problem of roadway support in Jinchuan mine is serious. The types of rockmass is classified based on engineering geological investigation data from in-situ rock mass,The in-situ stresses,deformation laws of surrounding weak rockmass,and support methods of roadway used in the mine are presented. Using rock bolt shotcrete and wire mesh support method as a primary support,immediate support can be provided to prevent the surrounding rockmass from loosening. The presented support method also permits the surrounding rockmass to deform gradually,so that the stress of surrounding rockmass can be released to certain degree. Rock bolting and grouting serves as a secondary support. Injecting the cement grout into the cracks of the rockmass can prevent the structure of the surrounding rockmass from loosening. Therefore the self-supporting ability of the surrounding rockmass is enhanced. Moreover,using rock bolting and grouting support combined with rock bolt shotcrete and wire mesh support,multi-layer-compounding arches can be formed to increase the effective load-carrying capacity. For the roadways under high in-situ stresses,if the surrounding rockmass is stratified fractured structure or loosening structure,the primary support should be rock bolt shotcrete and wire mesh support,and secondary support should be sectional fabricated steel arch,rock bolting and grouting support,reinforced concrete support,or rock bolting and grouting together with U shaped iron bar. Generally,these measures can serve to maintain the stability of the roadway. This new technology is gradually becoming popular in Jinchuan nickel mine.
Chinese Journal of Rock Mechanics and Engineering
rock mechanics,weak rockmass,engineering geology classification,deformation and failure laws,rock bolt shotcrete and wire mesh support,rock bolting and grouting support,combined support