摘要
深部巷道围岩变形破坏行为及理论模型研究对于我国深部开采工程具有重要意义.根据巷道附近围岩的受力特征,认为临近巷道的围岩经历了"三向应力→双向应力→近似单轴应力"作用过程,从而在巷道周围会形成应力梯度,而应力梯度是导致巷道围岩破坏的重要影响因素之一.通过不同应力条件下的围岩发生梯度破坏的宏观和细观特征,发现了随着深度增加,应力梯度更明显.根据宏细观破坏实验及数值分析,建立了深部巷道围岩破坏的梯度破坏理论模型,并给出了相对应力梯度与周围岩体提供的平均切向应力水平的关系.该模型表明:深部巷道围岩破坏跟所处的应力梯度场有很大的关系:靠近巷道的区域相对应力梯度越大而应力贡献度较小,该处岩体容易发生破坏;离巷道较远时,相对应力梯度接近零而应力贡献度上升,则趋于稳定,这是围岩松动圈理论的进一步发展.
Research on deformation, failure behavior and theoretical model of deep surrounding rock is significant for deep mining engineering. Based on the mechanics characteristic of sur- rounding rock, this paper illustrates that surrounding rock is subjected to triaxial stress, biaxi- al stress and approximate uniaxial stress respectively. Therefore, stress gradient will form a- round the tunnel. This paper indicates that the stress gradient is an important influence factor of surrounding rock failure in roadway. Macroscopic and mesoscopic characteristic of gradient destruction in different surrounding rock conditions have also been investigated. It has been found that the stress gradient play an important role in the surrounding rock deformation and failure process, which shows that the stress gradient would be stronger with an increasing depth. According to the macro-micro damage experiment and numerical analysis results, a rela- tionship between average shear stress level and relative shear stress gradient has been derived in detail. When the relative stress gradient near the roadway is larger but the stress contribu- tion is smaller, rocks at this location are prone to be damaged. When the relativelyslressgra dient far away from the roadway is close to zero while the stress contribution goes up. the sur- rounding rock is stable. This is a further development of broken rock zone theory.
作者
左建平
魏旭
王军
刘德军
崔凡
ZUO Jianping;WEI Nu;WANG Jun;LIU Dejun;CUI Fan(School of Mechanics and Civil Engineering,China University of Mining and Technology（Beijing）, Beijing 100083, China;State Key Laboratory of Coal Resources and Safe Mining, China University of Mining and Technology（Beijing）, Beijing 100083, China;School of Civil Engineering, Shandong Jianzhu University, Jinan, Shandong 250100, China 4. Beiiing Key Laboratory for Precise Mining of Associated Energy and Resources, Beijing 100083, China)
出处
《中国矿业大学学报》
EI
CAS
CSCD
北大核心
2018年第3期478-485,共8页
Journal of China University of Mining & Technology
基金
国家自然科学基金优秀青年基金项目(51622404)
国家自然科学基金(11572343)
国家重点研发计划项目(2016YFC0801404)
中国矿业大学(北京)越崎杰出学者计划
国家"万人计划"青年拔尖人才(WO2070044)联合项目
关键词
深部巷道
围岩
应力梯度
宏细观破坏
平均应力水平
应力贡献度
deep roadway
surrounding rock
stress gradient effect
macro/micro failure mech-anism
average stress level
stress cont ribution
