爆破振动对白马铁矿露天边坡稳定性影响研究

Impact research of blast vibration on stability of open pit slope in Baima iron mine

针对白马铁矿露天边坡的稳定性受爆破振动作用影响较大这一工程难题,本文基于数值仿真与现场监测等手段,结合强度折减法按照静力、边坡自重和爆破振动等相应特征研究,求解边坡应力、位移、安全系数在不同状态下的特点。结果表明:1)仅考虑边坡自重下时的临界强度折减系数为1.72,而爆破振动荷载作用时的临界强度折减系数为1.58,相对静力条件下爆破振动荷载作用时的强度折减系数减小了8.14%;2)构建水平振动速度与强度折减系数间关系,以此为基础求解了及及坪采场东部边坡安全振速为12.14 cm/s,临界振速为15.71 cm/s。本文研究成果可为同类金属露天矿山边坡稳定性判别分析、爆破振动对边坡的影响分析提供一定的借鉴与参考。

In view of the engineering problem that the stability of the open pit slope of Baima iron mine is greatly affected by blast vibration,based on numerical simulation,on-site monitoring and other means,the strength reduction method is combined to obtain the characteristics of slope stress,displacement and safety factor in different states according to the corresponding characteristics of static force,slope self-weight and blast vibration.The results show that:1)The critical strength reduction coefficient under the self-weight of the slope is 1.72,while the critical strength reduction coefficient under blast vibration load is 1.58,and the strength reduction coefficient under blast vibration load is reduced by 8.14%under relative static conditions.2)The relationship between horizontal vibration velocity and intensity reduction coefficient is constructed.On this basis,the safe vibration velocity of the eastern slope of Jijiping stope is 12.14 cm/s and the critical vibration velocity is 15.71 cm/s.The results can provide a certain reference for the discriminant analysis of slope stability and the influence of blast vibration on slope in similar metal open pit mines.