【作者】 何江；

【导师】 窦林名；

【作者基本信息】 中国矿业大学 ， 采矿工程， 2013， 博士

【摘要】 煤矿采动动载诱发冲击矿压显现的机理及防治，目前缺乏系统的研究。本文综合采用理论分析、现场原位试验、实验室试验、数值模拟及工程实践等研究方法，对煤岩力学特性的应变率相关性，煤矿采动动载特征、诱冲机理及降低动载作用的冲击矿压防治进行了系统研究。现场测试及研究表明：原岩应力是静载的基础，采掘空间附近应力具有基本分布形式。采掘活动及煤岩动力学响应是采动动载的主要来源。动载应变率与矿震能量成正相关关系，煤矿动载应变率一般不超过10-1/s级，据此对煤矿载荷状态进行了界定，并推导或给出了动载表达式。试验研究表明：煤岩强度、弹性模量均随应变率呈指数关系；煤岩破坏前后加载系统输入的能量随应变率呈指数增加，动态破坏时间急剧减小，冲击倾向性显著增强；静载较低时，煤岩破坏需要较强动载或多轮动载作用，表现为动载破坏形态，静载较高时，较低的动载可使煤样破坏，主要表现为静载破坏形态；煤岩声发射表现出较强的凯瑟效应；动载作用下，煤岩在峰值应力前已表现出剧烈损伤。理论研究表明：煤岩具有临界损伤因子，当损伤因子达到临界值时，煤岩表现为宏观破坏；静载作用下，煤岩具有裂纹扩展优势方向，损伤主要在局部范围内发生；增大主差应力，可增大裂纹扩展方向和可扩展裂纹长度范围；动载作用下，应力大小及方向随时间改变，煤岩裂纹扩展优势方向也随之改变，增大了煤岩损伤范围；动载幅值越大、频率越低、持续时间越长，煤岩体损伤越大；动静组合作用下，静载主要提供煤岩破坏的应力和能量基础，动载主要起触发损伤破坏的作用，同时输入部分能量；动载作用时，煤岩表现为损伤加剧、结构面解锁滑移、自由面产生反射拉应力等损伤失稳现象。研究提出了动静叠加的“力能解锁”冲击矿压机理，阐述了煤岩结构强度的各向异性对动静叠加的力能解锁提供的条件。从动静叠加和时变动力学角度构建了冲击矿压判别准则，解释了冲击矿压的滞后显现，分析了动载的扰动形式，阐明了煤岩具有临界抗扰动能力，并分析了冲击矿压力能积聚特征及几类典型的解锁模式。提出了冲击矿压动静结合的监测预警思想，并指出动载应从动载源、煤岩动载响应两方面进行监测，介绍了冲击矿压动载监测关键技术，分析了动载监测的前兆规律；提出了降低动载作用防治冲击矿压原理，通过降低动载源强度、降低动载传播特性、降低动载扰动效应，降低或减弱冲击显现；研究了降低动载的关键技术，提出了控制动载扰动效应的“弹性+整体+高强蓄能承载”巷道支护形式。研究成果在桃山煤矿进行了现场实践，结果表明基于降低动载作用的冲击矿压防治理论及技术效果明显。该论文有图111幅，表22个，参考文献225篇。更多还原

【Abstract】 The process of mining dynamic load inducing rock burst in coal mine lacks of systematicresearch at present. This paper using a combination research methods of theoretical analysis,in situ tests, laboratory tests, numerical simulation and engineering practice systematicallystudied the characteristics of mining dynamic load, mechanism of which in inducing rockburst and reducing the role of dynamic load in rock burst prevention.Studies have shown that in-situ stress field is the basis of static load, and the stress nearthe mining space has a basic form of distribution. The mining activities and coal-rock dynamicresponses of coal mining are the main sources of dynamic load. Dynamic loading strain rateand rock burst released energy have a positive correlation. Coal mining dynamic loading strainrate is generally not more than the level of10-1/s, accordingly the load states are defined ofcoal mine.Coal and rock strength and elastic modulus increase exponentially with loading strain rateincreasing, and the presses energy input the coal and rock samples before and after destructionexponentially increase with strain rate increasing, while the dynamic failure time decreasessharply, and burst tendency increase largely with strain rate increasing. When static load is low,the destruction of the coal samples needs a strong dynamic load or cyclic dynamic load of acertain intensity, while at a higher static load, smaller dynamic load can lead the coal sample todamage. The phenomenon of acoustic emission showed strong Kaiser effect in loading of coaland rock samples. Under dynamic load, the coal and rock samples have demonstrated a severefracturing before peak stress.When the damage factor reaches the critical value of coal or rock, the coal or rock willperformance of instant overall destruction. Under static load, the coal and rock havepredominant direction of crack propagation and damage occurred mainly in a local area. Therange of crack propagation direction can be increased by increases the principal differentialstress. Under dynamic loading, stress magnitude and direction change over time, while thecoal-rock crack propagation advantage direction is also changed, and the range of coal androck damage is increased. The larger the magnitude, the lower the frequency, and the longerthe duration of the dynamic load is, the greater the damage of coal-rock is. In the process ofrock burst, static load mainly provides the energy of coal and rock for damage and bursting,while the dynamic load mainly triggers damage to bursting. The dynamic load effect in rockburst formation is causing coal-rock to exacerbate damage, making the structural planedeblock to slip, and leading coal body near the surface reflect seismic wave to cause tensilestress to lead instability of coal and rock mass. Rock burst "Five Inducing Factors" is promoted in this work. Accordingly, the fivefactors interaction on a certain situation induces rock burst. From time-varying dynamics andthe static mechanics points of view, separately established criterions of rock burst whichexplained the lagging appearance of rock burst. The research work also analyzed thedisturbance form of dynamic load, stated the coal and rock critical antidisarrangement ability,revealed "force and energy deblocking" rock burst mechanism, presented the requirmentsprovided by the structural strength anisotropy of coal and rock, and analyzed several tipicaltypes of deblocking form.In rock burst monitoring and prevention, this paper promoted the thought of static anddynamic load combined monitoring, and pointed out that dynamic load should be observedfrom the source and the coal and rock response of dynamic load, and introduced rock burstmonitoring key technologies, and analyzed monitoring precursor law of rock burst underdynamic load, and proposed rock burst prevention principle by reduce effect of dynamic load,that is reducing the propagation and of effect of dynamic load so as to avoid or weaken rockburst, moreover, this paper also studied the key technologies of reducing dynamic load, andproposed the roadway support form of―elastic-overall-high strength and storage bearer".Finally, the research results were put to practice usage in the Taoshan coal mine. The practiceresults showed that the rock burst prevention and control theory and technologies based onreducing the effect of mining dynamic load has a remarkable effect.There are111figures,22tables and225references in this paper.更多还原