Focused on the blasting vibration in the blasting excavation of oversize dangerous rock mass,a numerical simulation model according to the characteristic of dangerous rock mass was established by FLAC3D,where the dangerous rock mass was divided into slices,and the blasting dynamic loads of different single dose were calculated and input to get the acceleration of mass point in each slices.Besides,equivalent acceleration method based on rigid limit equilibrium equation was adopted to analysis the stability of dangerous rock mass dynamic behavior,further to work out the relations between safety factor and single dose,finally the maximum single dose corresponding to suitable safety factor was obtained according to related standards.Improved blasting effect was testified by the site blasting experiments.In addition,with the relationship between vibration velocity and explosion center distance,the vibration velocity in required distance from explosive source could be considered as the site standards under the controlled charge quantity.%针对特大型危岩体爆破开挖治理过程中的爆破振动影响,建立符合危岩体特征的FLAC3D数值计算模型.将危岩体进行条块划分,计算并输入不同段药量时的爆破荷载,计算得到各条块质点加速度,并采用基于刚体极限平衡的等效加速度法进行危岩体爆破动力稳定性分析,得出了危岩体安全系数与单段药量之间的关系,结合相关规范给出了合适的安全系数所对应的单段最大药量.经现场爆破试验验证,可获得较好的爆破效果.通过分析危岩体爆破振速与爆心距的关系,提出了在控制药量条件下,采用特定爆心距处测点振速可作为现场监测控制标准.
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