煤矿超大断面硐室判别方法及其工程特征

Discrimination method and engineering characteristics of super large section chamber in coal mine

随着矿井大型化、井下机械化和智能化水平的提高,煤矿大型硐室的使用逐年增多,硐室断面增大导致其围岩变形破坏规律不同,控制技术和策略也相应改变。本文首先随机对国内外15个井工开采煤矿的29条主要硐室进行调研,统计其埋深、断面面积和围岩岩性等情况。然后,采用模糊综合聚类法,以硐室埋深、断面面积、单轴抗压强度和围岩完整性系数作为指标,建立基于模糊综合聚类法的硐室断面分类方法,将硐室断面分为超小、小、中等、大和超大共5类,并对所调研硐室中的超大断面硐室进行判别。最后,利用数值模拟和现场调研验证该判别方法的合理性和准确性,并探讨煤矿超大断面硐室的工程特征,即围岩变形破坏剧烈、多因素共同影响、围岩控制和施工难度大,为其围岩支护设计和稳定性控制提供指导。

With the enlargement of mines, the improvement in mechanization and intelligentization of underground mining, the use of large-scale chamber is on the yearly increase. The increase of chamber cross-section area results in different deformation and failure evolution of surrounding rock, and the control technology and strategy are also changed accordingly. In this paper, the random survey of 29 main chambers of 15 coal mines at home and abroad has been conducted, and their burial depth, cross-section area and surrounding rock lithology have been calculated. Then, a classification method of chamber cross-section based on fuzzy comprehensive clustering method has been established with the burial depth of chamber, cross-section area, uniaxial compressive strength and surrounding rock integrity coefficient as measurable indicators. The chamber cross-section has been divided into five categories based on the indicators: super-small, small, medium, large and super-large, and super-large ones among investigated chambers have been identified. Finally, the rationality and accuracy of the classification method has been verified through numerical simulation and field investigation, and the engineering characteristics of the super-large section of the coal mines have been discussed. Super-large section chamber has the characteristics of severe deformation and failure of surrounding rock, joint influence of multiple factors, and great difficulties in control and construction of surrounding rock. This study provides guidance for supporting design and stability control of surrounding rock for super-large section chamber.