金川深部典型岩石岩爆倾向性多因素综合评判

Multi-factorial Comprehensive Estimation for Jinchuan's Deep Typical Rockburst Tendency

以金川二矿区深部为研究对象,通过对其花岗岩等6种典型岩样进行峰前卸载等多种常规力学实验研究,结合现场勘察数据,采用基于岩性、围岩、应力条件等不同评判角度的单一岩爆判据:强度脆性系数法、Barton法、弹性应变能指数法和围岩质量RMR法,分别对6种典型岩样进行岩爆倾向性理论预测,并引入模糊数学综合预测方法,以上述各单一判据结果为指标,运用专家评估法确定因素影响权重,多因素系统评价金川二矿区的岩爆倾向性。结果表明,传统单一岩爆预测判据方法不适合金川特殊地质环境。采用模糊数学综合预测方法多因素系统分析发现,花岗岩、大理岩等6种岩样均具有弱岩爆发生倾向,其结果与现场符合较好,对矿山下阶段安全、高效生产中的岩爆防治有一定的科学指导意义。

The rocks in a deep mining area in Jinchuan 2nd mine are studied in this paper. Several mechanical experiments were conducted, including pre-peak loading and unloading, for six kinds of typical rocks, such as granite, marble and peridotite. Combined with the prospected data, different rockburst criteria, like the coefficient R method, Barton method, elastic strain energy index WET method and rock mass rating system method, are employed, respectively, according to different lithology and stress conditions to theoretically forecast the rockburst tendency of the rock mass. Fuzzy mathematics comprehensive prediction method is also used, with its index being based on each single criterion results, together with the expert-system evaluation method to determine the weight of every impact factor, to evaluate systematically the rockburst tendency of rock in Jinchuan No. 2 Mine. Results show that the single traditional rockburst forecast method is not suitable for the special geological environment in Jinchuan, while fuzzy mathematics comprehensive prediction method can provide better results. Six types of rock specimens, such as granite, marble, are of weak rockburst tendency, which are in accordance with the situ results. The forecast method proposed in this paper provides some guidance for preventing rockburst in mining excavation.