Activation mechanism and characteristics caused by normal fault damage under mining disturbance
陈太勇刘国磊常笑笑吴延成马秋峰郝喜庆赵成博
CHEN Taiyong;LIU Guolei;CHANG Xiaoxiao;WU Yancheng;MA Qiufeng;HAO Xiqing;ZHAO Chengbo
山东理工大学 资源与环境工程学院新汶矿业集团有限责任公司 孙村煤矿山东能源集团鲁西矿业有限公司 郭屯煤矿枣庄矿业集团 高庄煤业有限公司
为了探究工作面向正断层推采时断层力学响应特征,基于高庄煤矿1105工作面工程地质条件建立数值仿真模型,获得开采扰动下断层损伤变量演化特征;对模拟结果进行多元线性回归分析并建立下盘岩体力学模型,获得断层损伤变量与煤体应力的关系。结果表明:断层的裂隙损伤由高位岩层向低位岩层发展,当断层损伤变量达到临界值时,断层具备发生活化的条件;工作面采动影响下,断层损伤变量的发展早于煤体支承压力的增长,可将断层损伤变量作为预报断层活化、煤体应力升高的关键指标;通过多元线性回归分析确定的对断层损伤变量的影响因素依次为距断层距离、垂直应力、断层内摩擦角、断层黏聚力;工作面向断层推采过程中,工作面与断层间煤体宽度减小造成了煤体应力增加;同时推采导致了断层面的损伤发展,上下盘岩体之间有效承载面积减小,岩体质量大部分由下方煤体承担,煤体应力进一步增加。
In order to explore the mechanical response characteristics of faults when the working face is normal fault mining, a numerical simulation model is established based on the engineering geological conditions of 1105 working face in Gaozhuang Coal Mine to obtain the evolution characteristics of fault damage variables under mining disturbance. The simulation results are analyzed by multiple linear regression analysis and the mechanical model of footwall rock mass is established to obtain the relationship between fault damage variables and coal stress. The results show that the fracture damage of the fault develops from the high rock layer to the low rock layer. When the fault damage variable reaches the critical value, the fault has the condition to activate; under the influence of working face mining, the development of fault damage variable is earlier than the increase of abutment pressure of coal body. Fault damage variable can be used as a key index to predict fault activation and coal body stress increase; through multiple linear regression analysis, the determined influencing factors of fault damage variables are distance from fault, vertical stress, internal friction angle of fault and fault cohesion; in the process of working face to fault mining, the decrease of coal width between working face and fault causes the increase of coal stress. At the same time, the mining leads to the damage development of the fault surface, the effective bearing area between the upper and lower rock mass is reduced, the weight of the rock mass is mostly borne by the lower coal body, and the coal body stress is further increased.
正断层开采扰动断层活化损伤变量数值模拟多元线性回归分析
normal fault;mining disturbance;fault activation;damage variable;numerical simulation;multiple linear regression analysis
主办单位:煤炭科学研究总院有限公司 中国煤炭学会学术期刊工作委员会