中深埋缓倾斜梯形切眼围岩变形规律及支护技术  

Surrounding rock deformation law and support technology of moderately deep buried gently inclined trapezoidal cut

作　　者：于远祥[1] 廖安全 YU Yuanxiang;LIAO Anquan(College of Civil and Architectural Engineering,Xi’an University of Science and Technology,Xi’an 710054,China)

机构地区：[1]西安科技大学建筑与土木工程学院,陕西西安710054

出　　处：《西安科技大学学报》2023年第6期1137-1148,共12页Journal of Xi’an University of Science and Technology

基　　金：陕西省自然科学基础研究计划项目(2014JM2-5052);中国博士后科学基金项目(2015M582761XB)。

摘　　要：针对缓倾斜巷道在开挖扰动、孔隙水压及地应力共同作用下变形破坏的高度复杂性和难以控制的显著特点,以马蹄沟煤矿3506工作面缓倾斜梯形切眼为工程背景,基于弹塑性变形理论,建立了垂直地应力、水平构造应力及孔隙水压共同作用下切眼围岩受力计算模型。考虑开挖过程中切眼围岩内摩擦角与黏聚力的扰动劣化效应,推导了非均匀地应力场作用下切眼围岩的应力和位移解析解,进而针对性地提出了倾斜巷道开挖及其围岩支护方案。结果表明:开挖方式、地质强度、切眼倾角、地应力、孔隙水压及岩体应变软化程度是影响切眼围岩的应力分布与位移大小的关键性因素;倾斜巷道不同断面位置所受地应力和孔隙水压存在差异性,不同掘进区段围岩变形量并不相同,应设计不同的开挖预留量及其支护参数。最后,基于上述理论分析,将马蹄沟煤矿3506工作面缓倾斜切眼分为4个掘进区段,确定了切眼第一区段至第四区段掘进预留变形量分别为300,260,220及200 mm,切眼围岩支护加固后,其顶底板最大移近量为204 mm,两帮最大移近量为165 mm,围岩变形控制效果良好,满足现场生产要求。The deformation and failure of gently inclined roadway under the combined action of excavation disturbance,pore water pressure and in-situ stress is highly complex and difficult to control.Taking the gently inclined trapezoidal cut of the 3506 working face in Matigou coal mine as the engineering background,based on the theory of elastic-plastic deformation,a calculation model for the stress on the surrounding rock of the cut under the combined action of vertical geostress,horizontal tectonic stress and pore water pressure was established.Considering the disturbance degradation effect of friction angle and cohesion in the surrounding rock of the cut during excavation,the analytical expression of stress and displacement of the surrounding rock of the cut under the non-uniform geostress field were derived,and a targeted excavation and surrounding rock support scheme for inclined roadway was proposed.The results show that excavation method,geological strength,cut angle,geostress,pore water pressure,and degree of rock strain softening are key factors affecting the stress distribution and displacement of the cut rock mass;there are differences in ground stress and pore water pressure at different sections of inclined roadway,and the deformation of surrounding rock in different excavation sections is not the same.Therefore,different excavation reserves and support parameters should be designed.Finally,based on the above theoretical analysis,the gently inclined cut of the 3506 working face in Matigou coal mine was divided into four excavation sections,and the reserved deformation amounts for excavation from the first section to the fourth section of the cut were determined to be 300,260,220 and 200 mm,respectively.After the reinforcement of the cut surrounding rock support,the maximum displacement of the roof and floor of the surrounding rock is 204 mm,and the maximum displacement of the two sides is 165 mm,the deformation control effect of the surrounding rock is good,meeting the requirements of on-site production.

关 键 词：缓倾斜煤层 梯形切眼 预留变形量 支护技术 

分 类 号：TD353[矿业工程—矿井建设]