煤矿防冲支护装置高抗-快卸机理研究

Rock burst could result in column bending, inflation of cylinder, or cylinder head cracking etc., even more cause serious issues for coal mine safety. Thus, it is extremely urgent to carry out the supporting protection device research with high resistance - quick release feature. The key point is the high resistance - quick release mechanism. This research synthesizes multiple methods such as including field investigation, theoretical and numerical analysis, simulation and experimental analysis to study the interaction mechanism and rules between surrounding rock and support system when the rock burst impact occurs. This research could establish energy model when coal and rock mass occurs burst instability, and investigate the relationship among the energy release rate, the absorption rate and the supporting structure parameters under the magnitude of rock burst effect 0.1 to 0.5 through theoretical and experimental study. This research could explore the varying pattern of impact force along the bang path from the coal and rock, roof beams supporting equipment, hydraulic columns, and safety valve to the base. Using reverse principle value and experimental analysis, this study could investigate the critical peak of impact force and velocity which could lead to the typical failure of hydraulic support column. This study could carry out research that can detect the relationship between the new multi-level parallel fast high flow valve’s structure parameters and its dynamic characteristics, and analyze its high resistance - quick release mechanism. Even more, this research could establish selection criteria for flow valve to adapt to the different impact levels of rock burst, and provide a theoretical basis for the design of the supporting structure to mine rock burst in our country.

冲击地压导致防冲支护液压立柱失稳弯曲、胀缸、缸盖破裂事故。因此，研究高抗-快卸特性的煤矿防冲支护装置迫在眉睫，而高抗-快卸机理研究是问题关键。项目采用现场调研、理论分析、数值模拟、实验研究相结合的方法，研究冲击地压发生时，围岩与支护装置间的相互作用机理与规律。建立煤岩体发生冲击地压失稳的能量模型，理论与实验研究震级分别为0.1~0.5级冲击地压作用下冲击煤岩体的能量释放率、支护装置能量吸收率与防冲支护结构之间的相互关系。研究冲击力在煤岩体、支护顶梁、液压立柱、安全阀及底座传递路径上的变化规律。运用逆向原理数值与实验分析导致液压立柱典型失效形式的冲击力大小及速度临界峰值。开展新型多级并联快速大流量安全阀的结构参数优化，分析其高抗-快卸作用机理，建立适应不同级别冲击地压特性的大流量安全阀选用标准，为我国冲击地压矿井防冲支护装置设计提供理论依据。

冲击地压矿井安全开采是世界性难题，安全高效的冲击地压矿井防冲支护装置设计是冲击地压矿井煤矿安全生产亟待解决的重要问题。项目通过理论研究、数值模拟、实验室及现场实验研究等手段，围绕冲击地压发生时煤岩体与支护装置相互作用机理及规律开展研究，揭示了冲击地压发生时围岩与支护装置间的相互作用机理、防冲支护装置的高抗快卸吸能特性及冲击作用下围岩-支护系统的吸能防冲机理。项目主要研究成果如下：建立了冲击地压巷道扰动响应模型、含残余区的冲击地压巷道扰动响应模型，得到了解析解；根据冲击地压发生的扰动响应失稳判别准则对支护作用下巷道围岩的稳定性进行研究，分析了围岩的力学参数对支护强度、对围岩和支护系统稳定性的影响程度；分析了残余区的冲击地压巷道围岩-支护系统的影响规律。建立高压大流量安全阀的模型，分析了大流量安全阀开启过程的稳定性和工作特性，得到安全阀结构对高抗-快卸特性的影响规律。分析了预折纹诱导式、扩径式、直纹管扩径式和直纹管外翻式四种吸能构件的力学特性，进行了实验研究，得到了不同形式吸能构件的高抗快卸吸能特性。建立了考虑下落岩体重力的立柱液体冲击问题动力学波动方程及其定解条件，推导出立柱内液体运动解析式及液体压力解析式；建立了顶板来压和底板来压两种典型冲击地压形式下，吸能构件和立柱系统液体冲击定解问题的数学模型；建立了立柱-安全阀-吸能构件的联合吸能防冲模型，分析了吸能构件和安全阀间的协同吸能防冲特性。针对巷道支护设备及防冲支架核心关键部件的实验室冲击实验，自制6500kN静动复合加载液压冲击试验机，对防冲吸能立柱进行了动力学冲击试验，验证了防冲支架在冲击地压矿井巷道中的有效性。项目研究理论进行了成果转化并在内蒙古蒙大煤矿得到成功应用。以上成果的取得为解决冲击地压矿井防冲支护的技术难题提供了基础理论支持和实验手段。