单轨吊巷道顶板深梁支护结构的构建及应用
Deep beam support structure construction of roadway roof with monorail crane and its application
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摘要: 针对单轨吊作用下区段平巷顶板控制难题,提出将巷道顶板视为深梁进行稳定性分析,并采用密集布置的高预应力锚索和强力锚杆支护系统构建顶板锚固复合深梁承载结构。采用FALC3D数值模拟软件研究了余吾矿S1203回风巷实际支护参数条件下的顶板预应力场分布特征,揭示了单轨吊巷道顶板的成梁机制,得出S1203回风巷顶板深梁厚度为6 m。通过对S1203回风巷顶板进行受力分析,建立了单轨吊作用下巷道顶板锚固复合深梁承载结构的力学模型,根据应力叠加准则,推导出深梁内部最大剪应力分布表达式,据此结合Matlab数值分析软件得出顶板深梁最大剪应力分布随单轨吊载荷变化的响应规律,阐明了单轨吊作用下巷道顶板的稳定性控制机理。根据S1203回风巷的矿压观测结果,单轨吊作用前后巷道顶板均未出现离层现象,顶板最大下沉量及两帮收敛量不变,分别为72,48 mm,表明巷道顶板深梁支护结构的构建有效实现了单轨吊作用下巷道顶板的控制。Abstract: Aiming at the roof controlling problem of roadway which is under the action of monorail crane,the roadway roof is regarded as deep beam for stability analysis,and the dense arrayed high prestressed anchor cable and strength anchored bolt supporting system were applied to construct the composite rock-bolt deep beam bearing structure. FLAC3D software was also used to model the distribution characteristics of anchor cable prestressed field under the con- dition of actual support parameters of S1203 return airway of Yuwu Mine,and the beam forming mechanism of monorail crane roadway roof was revealed. The deep beam thickness of S1203 return airway roof was determined to be 6 m. Fur- thermore,the composite rock-bolt deep beam bearing structure mechanical model under the action of monorail crane was established with the analysis of roof sufferance force of S1203 return airway,and the expression of maximum shear stress distribution in deep beam was deduced according to stress impose theory. Combining Matlab software and the mechanical analysis above,the deep beam maximum shear stress distribution response laws with the change of monorail load was obtained,and the roof stability control mechanism under the action of monorail crane was clarified. According to the result on the observation of rock pressure of S1203 return airway,there were no roof separation after the action of monorail crane. The maximum roof subsidence and convergence of wall rock stays the same,and the values are 72 and 48 mm,respectively. The observation result shows that the construction of roof deep beam structure under the action of monorail crane is feasible and effective.