山东招远水旺庄金矿深部地应力特征及其岩爆倾向性分析

通过山东省招远市水旺庄金矿1881.08 m深孔水压致裂原地应力测量，获取了矿区深部地应力特征及其随深度的变化规律。结果表明：该矿区最大主应力随深度增加具有呈线性增大趋势，800.00 m以浅原位地应力状态以水平应力为主，随深度增加铅直主应力逐渐过渡为最大主应力；其中，最大水平主应力为11.22～45.69 MPa，最小水平主应力为7.28～36.17 MPa，铅直主应力为8.44～48.27 MPa，最大水平主应力方向为北西西向。根据该矿区应力量值及其最大水平主应力方向，分析了深部矿体地应力特征，水旺庄矿区深部地应力在招远−莱州地区属于一般偏低水平。结合钻孔岩芯岩石力学参数，基于工程岩体分级标准及岩石块体弹性应变能理论，对高围压环境下深部矿体开挖过程中，地下巷道发生岩爆的倾向性进行了分析讨论，水旺庄金矿总体属于无岩爆或弱岩爆的地层，但局部如1102.78 m、1379.40 m深度存在强烈岩爆倾向性，金矿矿体所处的1680.40~1684.90 m深度大体位于无岩爆区域。上述研究成果可为深部矿山建设与开采设计提供重要的科学依据。

In-situ stress characteristics and rockburst tendency of surrounding rocks in the Shuiwangzhuang gold deposit,Zhaoyuan, Shandong province

We carried out hydraulic fracturing in-situ stress measurements in an 1881-m deep borehole at the Shuiwangzhuang gold deposit and obtained the variation law of deep in-situ stress with depth in the mining area. The measurement results show that the maximum principal stress has an increasing linear trend with depth. The horizontal stress dominates the in-situ stress state within 800 m, and the vertical stress gradually transitions to the maximum principal stress with increasing depth. The maximum horizontal principal stress ranges from 11.22 to 45.69 MPa, the minimum horizontal principal stress from 7.28 to 36.17 MPa, and the vertical principal stress from 8.44 to 48.27 MPa; The direction of the maximum horizontal principal stress is NWW-trending. We analyzed the characteristics of the deep orebody’s in-situ stress according to the stress value and the direction of the maximum horizontal principal stress, which reveals that the deep in-situ stress of the Shuiwangzhuang mining area belongs to the generally low level in the Zhaoyuan–Laizhou area. We discussed the tendency of rockburst in the underground roadway during deep excavation under a high confining pressure environment based on rock mechanics parameters of drill cores, engineering rock grading standards, and elastic strain energy theory of rock bodies. The Shuiwangzhuang gold orebodies generally belong to the rockburst-free strata or strata with weak rockbursts. However, there is a strong rockburst tendency at depths such as 1102.78 m and 1379.40 m. The gold ore body is at a depth of 1680.40~1684.90 m, generally in the rockburst-free area. The above research results can provide an essential scientific basis for deep mine construction and mining design.