Xu Xuefeng, Dai Zuo, Xu Hao
School of Energy Science and Engineering, Henan Polytechnic University, Jiaozuo 454000, People's Republic of China.
Key Laboratory of Green and Efficient Mining and Comprehensive Utilization of Mineral Resources in Henan Province, Henan Polytechnic University, Jiaozuo 454000, People's Republic of China.
ACS Omega. 2024 May 24;9(22):23542-23554. doi: 10.1021/acsomega.4c00736. eCollection 2024 Jun 4.
The dynamic load resulting from the fracture of extremely thick rock layers directly influences the surrounding rock layers within stopes and roadways, thereby inducing rockburst disasters. Hence, studying the tunnel floor's impact and ground pressure induced by dynamic load disturbance under extremely thick conglomerates is crucial. This study focuses on the 23130 working face of Yuejin Coal Mine as its engineering background. Initially, through similar simulation experiments, the impact characteristics of dynamic load disturbance positions under thick conglomerates on tunnel bottom damage are investigated. Building upon this foundation, finite element numerical simulation is employed to explore the further conglomerate thickness' impact on tunnel floor damage under dynamic load disturbance. Lastly, the accuracy of similar and numerical simulation results is validated by incorporating field examples. Findings reveal that dynamic load disturbance leads to an instantaneous increase in coal and rock mass acceleration in the roof and floor of roadways, followed by a decrease to an equilibrium state, thereby subjecting the interior to high static load conditions. The thickness of conglomerate in the overlying rock layer emerges as a crucial factor affecting tunnel floor rockburst incidents. With dynamic load disturbance, as conglomerate thickness increases, the stress concentration area of the tunnel floor gradually shifts to deeper rock strata. Effective control of tunnel floor rockbursts can be achieved by implementing support measures like anchor rods and cables and managing tunnel deformation and damage under dynamic loads. Dynamic load disturbance under extremely thick conglomerates emerges as a pivotal condition for inducing tunnel floor impact damage. This study provides a theoretical foundation for the safe excavation of similar mine tunnels and for implementing rockburst prevention and control measures.
极厚岩层断裂产生的动载直接影响采场和巷道内的围岩，进而诱发岩爆灾害。因此，研究极厚砾岩下动载扰动对巷道底板的影响及地压至关重要。本研究以跃进煤矿23130工作面为工程背景。首先，通过相似模拟试验，研究厚砾岩下动载扰动位置对巷道底板破坏的冲击特性。在此基础上，采用有限元数值模拟方法，进一步探讨砾岩厚度对动载扰动下巷道底板破坏的影响。最后，结合现场实例验证相似模拟和数值模拟结果的准确性。研究结果表明，动载扰动导致巷道顶板和底板煤岩体加速度瞬间增大，随后减小至平衡状态，使内部处于高静载条件。上覆岩层中砾岩的厚度是影响巷道底板岩爆事故的关键因素。在动载扰动作用下，随着砾岩厚度的增加，巷道底板应力集中区逐渐向深部岩层转移。通过实施锚杆、锚索等支护措施，控制动载作用下巷道的变形和破坏，可以有效控制巷道底板岩爆。极厚砾岩下的动载扰动是诱发巷道底板冲击破坏的关键条件。本研究为类似矿山巷道的安全开挖及实施岩爆防治措施提供了理论依据。
