【作者】 赵志刚；

【导师】 谭云亮； 潘岳；

【作者基本信息】 山东科技大学 ， 采矿工程， 2007， 博士

【摘要】 本文运用理论分析、数值模拟和现场测试研究为一体的方法对煤与瓦斯突出的耦合灾变机制和非线性特征进行了研究。利用ANSYS/LS-DYNA软件的隐式-显式分析功能对应力波作用下巷道围岩的响应进行数值模拟，研究了应力波对煤与瓦斯突出的诱发作用。在应力波的作用下，巷道围岩中交替出现拉应力和压应力，随着应力波峰值的增大，巷道围岩的应力数值出现不同程度的增大。层裂体的形成和失稳破坏是煤与瓦斯突出发动的基本环节。运用断裂力学、有限元方法和自组织理论研究了瓦斯压力和应力波作用下单裂纹的扩展、相邻裂纹的贯通和层裂体的形成机理。研究发现，相邻的平行裂纹较易发生剪切贯通破坏和拉伸贯通破坏，影响裂纹贯通的因素有裂纹倾角、排列方式和间距；将卸载拉应力和瓦斯应力场产生的拉应力视为广义驱动力，探讨了裂纹演化过程中的非线性特征，统计表明，裂纹的长度与产生频率遵守幂率规则。将煤与瓦斯突出的过程简化为层裂体在地应力与瓦斯压力的耦合作用下发生失稳的过程，对层裂体失稳的准静态过程进行了折迭突变分析，计算了煤与瓦斯突出时释放的能量和煤与瓦斯突出的强度；给出了双曲扁壳层裂结构的动力学方程的统一形式，发现随着动力扰动和瓦斯压力的增大，层裂体的演化经历了从周期1、周期2、周期3到混沌的过程。进行了煤与瓦斯突出的混沌动力学唯象研究，基于现场实测数据识别出煤与瓦斯突出孕育过程中的混沌吸引子，利用C-C方法计算了时间延迟和嵌入维数，发现有突出危险的瓦斯浓度监测序列的△(?)-τ_s曲线与无突出危险的△(?)-τ_s曲线存在明显的不同；计算了关联维数和最大Lyapunov指数，发现突出的危险性与瓦斯浓度时间序列的关联维数和最大Lyapunov指数有较强的关联性。基于混沌理论，对煤与瓦斯突出孕育过程中的监测数据序列预测方法进行了研究，研究表明，全域法、零阶局域法的预测精度较低，而一阶加权局域法和基于Lyapunov指数的预测方法预测精度较高。更多还原

【Abstract】 Based on theoretical analysis, numerical simulation and filed-testing, the coupling catastrophe mechanism and nonlinear characteristics of coal and gas outbursts are studied in this dissertation.Using the implicit-explicit analytical function of ANSYS/LS-DYNA, the response of laneway surrounding rock under the stress wave is simulated and the induced effect of stress wave is studied. It is found that, under stress wave, tensile stress and compressive stress will occur in laneway surrounding rock and the stress value would increase along with the increase of stress wave intensity.The formation and instable failure of layer-crack structure is the crucial step of coal and gas outburst. Based on fracture mechanics, FEM and self-organization theory, the expansion of single crack, the breakthrough of adjacent parallel cracks and forming mechanics of layer-crack structure under the gas pressure and stress wave are studied. The study indicates that adjacent parallel cracks are broken easily by shearing breakthrough and tensile breakthrough. The factors which affect breakthrough are crack inclination, permutation style and crack distance. The tensile stress generated by unloading and gas stress field can be considered as generalized driving force, by which the non-linear feature in the crack evolvement is analyzed, and the statistic indicates that the length and generating frequency obey the power rule.The procedure of coal and gas outburst can be simplified as the destabilization procedure of the layer-crack structure under the coupling function of crustal stress and gas pressure. The quasistatic process of destabilization of the layer-crack structure is analyzed by the fold catastrophe theory. Then released energy and strength when coal and gas outburst happened are calculated. Moreover, the unified dynamic equation of hyperbolic shallow layer-crack structure is established, and it is found that, along with the increase of dynamic perturbation and gas pressure, layer-crack structure goes through the evolution of from period 1, period 2, and period 3 to chaos state.Phenomenological study is carried out. The chaos attractor of coal and gas outburst in gestation process is identified by analyzing local data. Time delay and embed dimension are calculated using C-C method, subsequently correlation dimension and the largest Lyapunov exponent are calculated. It is discovered that the possibility of coal and gas outburst is closely correlated with correlation dimension and the largest Lyapunov exponent.Based on chaos theory, the prediction method for time series of monitoring data in the process of coal and gas outburst gestation is studied, and results indicate that the prediction accuracy of global region method and zero-order local region method is low, but to adding-weight one-rank local-region method, the reverse is true.更多还原