摘要:
煤矿冲击地压是煤岩系统产生失稳引发的岩石动力灾害，为进一步探寻冲击地压的产生机理，
针对冲击地压的动力时变特性，从动力系统的角度出发，结合时变力学原理分别对煤岩试件-试验机系统、顶板煤柱系统、巷道围岩系统进行了参数辨识。得到了外部扰动时变、内部参数时变和外载时变3种不同时变类型影响下的系统参数变化规律，建立了煤岩时变系统的动力方程，证明了煤岩系统失稳引发冲击地压是一个时变问题。进一步分析了不同煤岩系统的时变特点，得到时变系统满足叠加性、均匀性、能控性、能观性的判别方法，并基于李雅普诺夫稳定性理论分析了煤岩时变系统稳定性，应用冻结系数法结合工程背景对稳定和非稳定煤岩时变系统的受扰状态进行了分析。结果表明：对于稳定的时变系统施加简谐扰动，系统的位移及速度响应呈现衰减振动的趋势，最后达到渐进稳定的状态；稳定煤岩系统由于内部参数时变可由稳定系统演变为非稳定煤岩系统，在简谐扰动下系统响应不断放大直至系统失稳引发冲击。进一步分析了煤岩系统的边界时变问题，得到了边界时变下巷道围岩弹性区、塑性区、破裂区3个子系统的系统稳定度时变规律，将时变力学原理应用于冲击地压领域，提出了煤岩系统失稳引发冲击地压的简单判据。
Abstract:
Coal mine rockburst is a rock dynamic disaster caused by instability of coal rock system. In order to further explore the mechanism of rockburst, based on the dynamic time-varying characteristics of rockburst, from the perspective of dynamic system, combined with the principle of time-varying mechanics, the parameters of the coal and rock specimen-testing machine system, roof-pillar system and roadway surrounding rock system were identified. The variation laws of system parameters under the influence of three different time-varying types of external disturbance, internal parameter and external load were obtained, and the dynamic equation of coal-rock time-varying system was established, which proved that the rockburst caused by instability of coal-rock system is a time-varying problem. The time-varying characteristics of different coal-rock systems were further analyzed, and the discriminant methods of time-varying system satisfying superposition, homogeneity, controllability and observability were obtained. The stability of coal-rock time-varying system was analyzed based on Lyapunov stability theory. The disturbed state of stable and unstable coal-rock time-varying system was analyzed by freezing coefficient method combined with engineering background. The results show that the displacement and velocity response of the system show a trend of attenuation vibration and finally reach a gradually stable state when simple harmonic disturbance is applied to a stable time-varying system. Because of the time-varying internal parameters, the stable coal-rock system can evolve from a stable system to an unstable coal-rock system. Under the simple harmonic disturbance, the system response enlarges continuously until the system destabilizes and causes rockburst. The problem of time-varying boundary of coal-rock system is further analyzed, and the time-varying law of system stability of three subsystems of the surrounding rock elastic zone, plastic zone and fracture zone under the boundary are obtained. The time-varying mechanics principle is applied to the field of rockburst, and a simple criterion of rock burst ground pressure caused by instability of coal-rock system is put forward.
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