煤矿斜井冻结段受力特征及井壁开裂原因分析  

Analysis on Stressed Features of Freezing Section and Cracking Causes of Shaft Lining in Mine Inclined Shaft

作　　者：郑天斌 周恒 ZHENG Tianbin;ZHOU Heng(Shanxi Zhongneng Coalfield Company Limited,Yulin 719000,China;State Key Laboratory for Geomechanics and Deep Underground Engineering,China University of Mining and Technology,Xuzhou 221116,China)

机构地区：[1]陕西中能煤田有限公司,陕西榆林719000 [2]中国矿业大学深部岩土力学与地下工程国家重点实验室,江苏徐州221116

出　　处：《建井技术》2020年第2期7-12,6,共7页Mine Construction Technology

摘　　要：袁大滩煤矿副斜井由明槽段、冻结段和基岩段3部分组成,总长度3555 m。其中冻结段(681 m)采用双层钢筋混凝土井壁,其断面为直墙拱顶、平直底板结构形式。副斜井冻结段施工完毕,底板即出现纵向裂缝,伴随多个出水点;通车后,底板裂缝进一步发展,并出现横向裂缝。为确保斜井井筒的长期安全稳定,对斜井井筒受力特征进行分析,找出该结构形式下的潜在危险点,并分析裂缝产生和发展的原因,评价井筒结构的安全性,为矿井运营和后期维护提供参考。数值模拟结果表明:(1)现有的井筒断面结构存在6处危险点,且各危险点处主应力值均呈现随埋深的增加而增大的趋势;(2)井筒断面的最大主应力云图基本稳定,但是最小主应力云图随着埋深的增加而逐渐变化,最大主应力表现为压应力,最小主应力表现为拉应力;(3)在不考虑车辆荷载往复作用对井筒应力的影响情况下,应力变化幅度随着埋深的增加而减小,不同危险点的变化幅度有所不同:拱顶变化幅度最大,而拱腰则没有应力改善;(4)直墙拱顶的结构是合理的,但平直底板的设置带来了结构的安全性问题,在围岩应力和往复车辆荷载的共同作用下,造成了裂缝的产生和贯通。An auxiliary mine inclined shaft of Yuandatan Mine was consisted with three sections,including the open cut section,freezing section and base rock section and the total length of the inclined shaft was 3555 m.Among them,the double reinforced concrete shaft lining was applied to the freezing section with a length of 681 m and the cross section of the freezing section was consisted with a vertical wall and arch roof,a flat floor structure.After the freezing section of the mine inclined shaft constructed,there were longitudinal cracking occurred in the floor and several water outlet points occurred.After the mine cars operated,the cracking in the floor of inclined shaft were further developed and the transverse cracking were occurred.In order to ensure a long term safety and stability of the mine inclined shaft,an analysis was conducted on the stressed features of the mine inclined shaft.The potential danger pints under the structure model were found and the analysis was conducted on the occurrence and development causes of the cracking.The safety of the mine shaft structure was evaluated and could provide the references to the mine operation and the late maintenances.The numerical simulation results showed that(1)the cross section structure of the existed mine shaft had six(6)dangerpoints,the major stress value of each danger point would be in a increasing tendency with the depth of the mine shaft increased.(2)The max major stress nephogram of the mine shaft cross section would be stable basically,but the min major stress nephogram would be steadily changed with the depth of the mine shaft increased.The max major stress would be a compressive stress and the min major stress would be a tensile stress.(3)Without consideration on the load reciprocating role of the vehicle affected to the stress of the mine shaft,the stress varied range would be reduced with the depth increased.The varied range of each danger point would be different.The varied range of the dome roof would be max and the haunch would not be improved.(4

关 键 词：斜井冻结 平直底板 井壁开裂 应力状态 车辆荷载 

分 类 号：TD265.32[矿业工程—矿井建设]