基于熵权-功效系数法的岩爆烈度分级预测研究

岩爆是高地应力区开挖过程中常遇到的工程地质灾害,发生突然且破坏性极大,因此岩爆的预测一直是岩爆课题的研究热点。在综合分析岩爆影响因素的基础上,选取切向应力与单轴抗压强度比值σθ/σc、岩石脆性系数σc/σt、围岩弹性储能Wet及岩石完整性系数Kv作为评价指标,将熵权法与功效系数法进行结合,采用熵权法确定各指标权重,并利用功效系数法进行综合评价,从而建立出岩爆预测的熵权-功效系数法模型。利用国内外17组典型工程实例对模型进行验证,将所得结果与功效系数法、熵权-正态云模型、RS-TOPSIS模型预测结果及实际情况进行对比。为进一步考查模型的适用性,利用该模型对猴子岩水电站及锦屏二级水电站进行岩爆烈度等级预测。研究结果表明,熵权-功效系数法模型能够综合考虑影响岩爆发生的主要因素,预测准确性较高且原理简单易懂,具有一定的工程运用前景。

STUDY OF PREDICTION OF ROCKBURST INTENSITY BASED ON ENTROPY AND EFFICACY COEFFICIENT METHOD

Rockburst is one of the main geological hazards encountered during excavation in high ground stress area. It happens suddenly and sometimes may bring devastating consequence. Therefore, rockburst prediction is always a hot research topic of rockburst subject. On the basis of comprehensive analysis of influencing factors of rockburst, the stress coefficient of rock σθ/σc, the brittleness coefficient of rock σc/σt, the elastic energy index of rock Wetand the integrality coefficient of rock Kvare selected as evaluation indices. By adopting entropy method to determine the weighting coefficient of each evaluation index, and using efficacy coefficient method to evaluate four indices comprehensively, the entropy-efficacy coefficient method model of rockburst intensity prediction is established. Using 17 groups of typical engineering examples at home and abroad to verify this model, and the results are compared with the prediction results of the efficacy coefficient method, the entropy and normal cloud model, the RS-TOPSIS model and practical situation. To further verify the practicability, this model has applied to rockburst intensity prediction of Houzaiyan hydropower station and Jinping II hydropower station. The research result shows that the entropy-efficacy coefficient method model which is easy to understand can evaluate main factors influencing rockburst comprehensively and possesses high prediction accuracy. Therefore, this model possesses certain prospect of engineering application.