School of coal engineering, Shanxi Datong University, Datong, Shanxi, China.
PLoS One. 2020 Jul 15;15(7):e0234071. doi: 10.1371/journal.pone.0234071. eCollection 2020.
The objective is to study the design method of roadway support and provide technical support for coal mining and other mining methods that need deep roadway excavation. Through literature review, the occurrence, development mechanism and influencing factors of surrounding loose rock zones of roadways are analyzed. A method of detecting is selected according to the characteristics of surrounding rock loosening. Knowledge of elastoplastic mechanics is used to theoretically study the failure mechanism of surrounding rock in deep re-mining roadways. Based on the artificial neural network prediction model (ANN), the surrounding rock is classified and a support network model of the decision system is constructed. After the design of roadway support, a sharp change of vault subsidence normally occurs within about 7 days after excavation, and the total subsidence is 14 mm. In the following month, deformation is slow, subsidence is small, and it is basically stable after one month. The curve of the vault subsidence rate shows that the vault subsidence rate is less than or equal to 1mm/d after 7 days. The convergence rate is also less than 1 mm/d after 7 days. There are two cave mouths AB and CD, and the convergence value of AB is 6.47mm, CD is 10.26mm: CD is slightly larger than AB, and it is close to stable one month later. It is essentially consistent with the time of vault settlement and stability, and the amount of deformation is approximately the same. This shows that, with the advance of the working face, the displacement of the surrounding rock in the section away from the working face will gradually decrease and the surrounding rock will be stable. The stability time of surrounding rock displacement of the portal section is the same as that of vault subsidence under the initial support, and the amount of deformation is approximately the same, indicating that the support parameters and construction methods are reasonable.
目的是研究巷道支护的设计方法，为需要深巷挖掘的采煤和其他采矿方法提供技术支持。通过文献回顾，分析了巷道围岩松动区的发生、发展机制和影响因素。根据围岩松动的特点，选择了一种检测方法。利用弹塑性力学知识，从理论上研究了深部再采巷道围岩的破坏机制。基于人工神经网络预测模型（ANN），对围岩进行分类，并构建决策系统的支护网络模型。进行巷道支护设计后，在开挖后约 7 天内，拱顶沉降通常会发生急剧变化，总沉降为 14 毫米。在接下来的一个月里，变形缓慢，沉降较小，一个月后基本稳定。拱顶沉降率曲线表明，7 天后拱顶沉降率小于或等于 1mm/d，收敛率也小于 1mm/d。有两个洞口 AB 和 CD，AB 的收敛值为 6.47mm，CD 为 10.26mm：CD 略大于 AB，一个月后接近稳定。它与拱顶沉降和稳定的时间基本一致，变形量大致相同。这表明，随着工作面的推进，远离工作面的围岩位移会逐渐减小，围岩会稳定。洞口段围岩位移的稳定时间与初始支护下拱顶沉降的时间相同，变形量大致相同，表明支护参数和施工方法合理。
