大断面厚顶煤巷道顶板冒落破坏的上限分析  

Upper bound limit analysis of roof collapse mechanism of large section roadway with thick top coal

作　　者：王琦[1,2,3] 王洪涛[1] 李术才[1] 王德超[1] 江贝[1] 张红军[1] 李为腾[1] 

机构地区：[1]山东大学岩土与结构工程研究中心,济南250061 [2]山东省矿山灾害预防控制国家重点实验室培育基地,山东青岛266590 [3]兖矿集团有限公司博士后科研工作站,山东邹城273500

出　　处：《岩土力学》2014年第3期795-800,共6页Rock and Soil Mechanics

基　　金：国家自然科学基金(No.51304125;No.51379114);中国博士后科学基金面上资助(No.2013M540548;No.2012M511028);矿山灾害预防控制国家重点实验室培育基地开放基金(No.MDPC2012KF11);山东省博士后创新项目专项资助(No.201301004);高等学校博士学科点专项科研基金-新进教师类(No.20130131120090)

摘　　要：根据大断面厚顶煤巷道顶板的破坏特性,考虑了顶板围岩应力水平与支护荷载的影响,利用Hoek-Brown强度准则及其相关联的流动法则,构造出厚顶煤巷道顶板的冒落破坏机构。基于塑性力学中的上限分析方法,结合变分原理,推导得到了大跨度厚顶煤巷道顶板的冒落破坏机制,并以赵楼煤矿某巷道现场实践为例,分析了不同计算参数对顶板冒落破坏机制的影响。计算研究表明:随着岩体经验参数A、抗拉强度、抗压强度及支护荷载的增加,冒落体尺寸随之增大,而当岩体经验参数B、围岩应力及岩体重度增加时,冒落体尺寸则随之减小;冒落体尺寸代表了巷道顶板安全性能的大小,其尺寸越大,表明使巷道顶板发生冒落破坏所需外力功越多,顶板安全性能也越高;岩体经验参数B、围岩应力水平与支护荷载对顶板围岩破裂机制影响较为显著,参数B决定了冒落体的破裂形状,随着参数B的增加,冒落破裂迹线的曲率不断减小;增大支护阻力是提高顶板稳定性的有效途径,其研究结果可为大断面厚顶煤巷道支护设计提供一定的理论依据。According to roof collapse characteristics of large section roadway with thick top coal, a failure mechanism of roof collapse block, considering the influences of the stress of surrounding rock and supporting pressure, was constructed based on Hoek-Brown failure criterion and its associated flow law. Through upper bound limit analysis, the roof collapse mechanism of large section roadway with thick top coal was deduced with variational principle;and with one roadway in Zhaolou coal mine, for example, the influences of rock parameters on roof collapse mechanism were also analyzed. The calculation results show that： With the increasing of empirical parameter A, tensile strength, compressive strength and supporting pressure, the size of collapse block increases, while decreases with the increasing of empirical parameter B, the stress of surrounding rock and unit weight of rock mass. The size of collapse block represents the roof stability, larger size means more external work to expend, and the roof is more stable. The parameter B, the stress of surrounding rock and supporting pressure have significant impacts on roof collapse mechanism;and the parameter B determines the shape of failure curved surface; the curvature of failure surface will decrease with the increase of parameter B. Improving supporting pressure is an effective way to increase the roof stability, which provides theoretical basis for the support design of large section roadway with thick top coal.

关 键 词：厚顶煤 顶板 HOEK-BROWN强度准则 塑性上限分析 围岩应力 

分 类 号：TD353[矿业工程—矿井建设]