深部采动巷道围岩塑性区演化规律与围岩失稳机理研究

As coal mining goes deeper and deeper, the surrounding rock stability control of deep mining-affected roadway has greatly restricted the coal mine productivity and threatened the coal mining safety. Centering on surrounding rock plastic zone emergence and development law of deep mining-affected roadway, this project will obtain deep mining-affected roadway surrounding rock stress-strain law and establish a constitutive model to represent surrounding rock deformation; according to the deep mining-affected roadway surrounding rock deformation and plastic zone development characteristics which are acquired by similar simulation experiment under self-developed Large-Scale Deep Coal Mine True Triaxial Test System, we will study deep mining-affected roadway surrounding rock plastic zone emergence and development law which is affected by stress environment and surrounding rock occurrence condition; Based on Tyson polygon network, the mining-affected roadway numerical simulation model is set up, and the Fish language development program is adopted to identify and extract the plastic zone emergence and expansion properties, then the stable-to-instable limit load and mechanics of mining-affected roadway surrounding rock plastic zone are analysed; meanwhile, by exploring the unsteady development law of surrounding rock plastic zone, the mechanical essence of deep mining-affected roadway surrounding rock deformation failure is revealed. Thus, on the basis of field test study, deep mining-affected roadway surrounding rock stability control method is put forward.

随着煤炭开采的深部发展，深部采动巷道围岩稳定性控制问题已严重制约煤矿生产能力，威胁煤矿安全。本项目将以深部采动巷道围岩塑性区产生和边界扩展规律为主线，在现场测试和实验室实验的基础上，获得采动巷道围岩采动应力下的应力应变规律，构建表征围岩变形规律的本构模型；结合通过自主开发的大型深部矿井真三轴试验系统的相似模拟实验获得的深部采动巷道围岩变形和塑性区的演化特征，研究应力环境和围岩赋存条件等因素影响下的深部采动巷道围岩塑性区形成和边界扩展的演化规律；结合泰森多边形网络建立采动巷道数值模拟模型，利用Fish语言开发专用程序对模拟过程中塑性区产生和扩展特征进行识别和提取，分析采动巷道围岩塑性区由稳态向非稳态转化的临界载荷和力学机制；研究围岩塑性区非稳态扩展规律，揭示深部采动巷道围岩变形失稳破坏的力学本质。在现场试验研究的基础上提出深部采动巷道围岩稳定控制方法。

深部采动巷道围岩普遍存在变形量大和变形时间长的问题，是长期困扰深部煤矿开采的难题之一。本项目采用大数据分析方法，分析了巷道围岩变形影响因素，得出了埋深对于巷道围岩变形影响拟合公式，得到了巷道围岩的岩性统计分布规律，及其对巷道变形的影响；研究了巷道断面大小和围岩变形量的关系及地温变化对于巷道变形的影响规律。建立了高应力条件下层状围岩巷道数值和物理模拟模型，模拟研究了深部高应力层状围岩巷道围岩表面和内部变形特征。建立了不同倾角的层状围岩巷道数值模拟模型，模拟分析不同岩层倾角的对围岩变形特征的影响规律。研究了巷道围岩不同部位变形显现时机差异和变形量不同的规律，揭示了围岩内部裂纹发育规律。开展了层状围岩巷道塑性区发育特征与应力分布实验研究，提出了采用应力监测结果反演塑性区分布规律的方法。推导了支护阻力对塑性区范围和围岩位移的影响的计算公式，以及圆形巷道蝶形塑性区的出现条件和塑性区非稳态扩展规律。提出了基于巷道围岩塑性区稳态控制的深部采动巷道围岩稳定控制方法。并结合提升围岩力学性能、优化围岩应力和支护结构强化等方法，建立阻止深部采动巷道围岩塑性区非稳态扩展的支护方式体系，并在江西丰城和湖南煤业等矿业集团中的采动巷道进行现场工业性试验研究，取得了良好的围岩稳定控制效果。