基于强度折减法的节理岩质边坡稳定性分析

Stability analysis of jointed rock slope based on strength reduction method

边坡稳定性直接关系到露天金属矿山的安全开采,鹿鸣露天矿采区北帮、东北帮边坡节理裂隙发育,一直处于缓慢变形的状态,为分析该采区稳定性,本文根据工程地质条件、边坡几何形状和边坡面倾向等要素,进行了采场边坡分区。采用FLAC 3D软件在研究区域选取2个典型剖面进行了边坡稳定强度折减法分析。结果表明:北区节理岩质边坡剖面处于极限平衡状态,风化岩层的赋存状态及边坡高度对边坡的安全有较大影响,需重点关注风化岩层及局部破碎岩体,塑性应变区主要集中在顶部风化二长花岗岩层,范围较为集中,使边坡发生局部性破坏。东北区剖面处整体稳定性相较北区高,塑性应变区主要集中在碎裂状二长花岗岩层与块状二长花岗岩层,且贯通为连续塑性滑移带,使边坡发生整体性破坏。

To analyze the stability of the mining area,the stope slope partition was carried out according to the engineering geological conditions,slope geometry and slope surface inclination.The results show that the jointed rock slope profile in the northern area is in the ultimate equilibrium state,and the occurrence state and slope height of the weathered rock layer have a great impact on the safety of the slope,so it is necessary to pay attention to the weathered rock layer and the local broken rock mass,and the plastic strain zone is mainly concentrated in the top weathered monzogranite layer,which is relatively concentrated,resulting in local failure of the slope.The overall stability of the section in the northeast area is higher than that in the north area,and the plastic strain zone is mainly concentrated in the 3-2-1 fragmented structure monzogranite layer and the 3-2-2 block structure monzogranite layer,and the continuous plastic slip zone is penetrated,resulting in the overall failure of the slope.