摘要
岩爆是深部高地应力区岩体开挖过程中常见的一种复杂的动力失稳现象。由于影响因素众多,且各因素在岩爆的孕育过程中所起的作用尚不十分明确,可以将岩爆与其影响因素间的复杂关系当作灰色系统,利用灰色聚类方法进行研究。根据岩爆的成因及特点,选取洞壁围岩的最大切应力、单轴抗压强度c、单轴抗拉强度t及岩石弹性能量指数et W作为影响岩爆的主要因素,并以应力系数/c、脆性系数c/t及弹性能量指数et W作为评价指标,通过对灰色白化权函数进行优化,建立改进的岩爆预测灰评估模型。该模型解决了传统模型存在的灰类多重交叉性及不满足规范性等问题,理论上更完备。采用改进模型对国内外若干深部岩石工程岩爆初始数据进行研究,并与传统模型的预测结果进行对比,发现改进模型的结果与实际情况吻合更好,预测精度更高,从而验证了改进模型的有效性及实用性。研究方法为岩爆的准确预测提供一种切实可行的途径。
Rockburst is a complicated dynamic instability phenomenon during the rock excavation of deep rock masses in high in-situ stress zone. It is affected by many factors,and the roles of various factors in the formation process of rockburst are not yet clear. Then,the complex relationship between rockburst and its influencing factors is considered as a grey system,which can be studied by the grey clustering method. According to the causes of rockburst and its characteristics,the main factors of rockburst,which are the maximum tangential stress of the cavern wallσθ,uniaxial compressive strength cσ,uniaxial tensile strength tσand the elastic energy index of rock etW ,are chosen in the analysis. Moreover,the evaluation indexes including the stress coefficient of rockσθ/σc , the brittleness coefficient of rockσc/ tσ,and the elastic energy index of rock etW are used to establish the modified grey evaluation model for rockburst prediction through the optimization of grey whitenization weight function. Compared with the traditional grey evaluation model,the modified model doesn′t have the crossing properties of grey cluster and meets the normality well,which is more reasonable in theory. Based on the rockburst data of some deep rock projects at home and abroad,the modified model is adopted to predict the possibility and classification of rockburst. Compared with the traditional model,the prediction error of the modified model is smaller. In addition,the prediction results of the modified model are close to the practical records,which proves that the model is effective and available. Therefore,the proposed method provides a practical way to accurately predict the possibility and classification of rockburst in deep underground engineering.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2013年第10期2088-2093,共6页
Chinese Journal of Rock Mechanics and Engineering
基金
国家重点基础研究发展计划(973)项目(2010CB732001)
国家杰出青年基金项目(51025935)
国家自然科学基金面上项目(51174190)
关键词
岩石力学
岩爆
高地应力
灰色系统
灰色聚类法
预测
rock mechanics
rockburst
high in-situ stress
grey system
grey clustering method
prediction
