破碎围岩结构面特征及稳定性分析

Structural plane characteristics and stability of broken surrounding rocks

为评价某金矿极破碎围岩的稳定性,测量并分析该矿围岩Ⅳ、Ⅴ级微型裂隙结构面,选取+260、+295、+330 m等3个生产中段;利用详细测线法分析节理间距、产状、起伏形态、粗糙度、张开度、渗水性对围岩稳定性的影响,使用极点图、玫瑰花图探讨优势结构面产状的分布特性。结果表明:该矿围岩节理裂隙较发育,节理分布较为紧密,平均间距小于1 m,且主要集中在0.2~0.6 m,围岩整体属于破碎、极破碎岩体,稳定性较差;该矿+260、+295和+330 m中段的产状优势结构面相似,都具有明显集中现象,倾向主要集中在324~360°和0~35°,倾角主要集中在70~79°;结构面的起伏状态多为平直型,对结构面稳定性影响较大;结构面之间结合较为紧密,填充物较少,对结构面的稳定性影响较小。

In order to evaluate the stability of extremely fractured surrounding rocks in a gold mine,micro-fracture structural planes of the IV and V grade of the surrounding rocks in the mine were measured and analyzed in three production sections of+260,+295 and+330 m.The influences of joint spacing,occurrence,undulating shape,roughness,openness and seepage on surrounding rock stability were analyzed by scanline method.The distribution characteristics of dominant structural planes occurrence were discussed by using pole plot and rose plot.The results show that the surrounding rock joints are well developed and closely distributed,and the average spacing is less than 1m and is mainly concentrated in 0.2-0.6 m.The surrounding rocks are broken and extremely broken rock mass with poor stability.The dominant occurrence has obvious concentration in the middle of+260,+295 and+330 m.The dip is mainly concentrated at 324-360°and 0-35°,and the dip direction is mainly concentrated at 70-79°.The undulating state of the structural plane is mostly straight,which has a great influence on the stability of the structural plane.The structural surfaces are tightly combined with less filler,which has less influence on the structural surface stability.