二次采动影响下锚索桁架联合支护技术的研究

Study on Combined Support Technology of Anchor Cable Truss under the Influence of Secondary Mining

以永安煤矿西三中间巷为研究对象,对预应力桁架锚索被应用于采动垮冒煤巷的支护机理进行了分析。运用中性轴理论分析了顶板在无支护条件下以及采取预应力桁架锚索支护后顶板内部受力情况及支护前后拉压应力区的变化情况,确定了桁架锚索合理的底部跨度以及合适预应力大小的计算方法。对永安煤矿西三中间巷采用了桁架锚索联合支护设计方案,监测数据理想,该支护设计可以较好地控制巷道变形问题。

Taking the Xisan Middle Roadway of Yong’an Coal Mine as the research object,the supporting mechanism of prestressed truss anchor cable applied to mining caving roadway is analyzed.Based on the neutral axis theory,the internal force of the roof and the variation of the tension and compression stress zone before and after the support are analyzed under the condition of no support and the prestressed truss anchor cable support,and the reasonable bottom span of the truss anchor cable and the calculation method of the appropriate prestress are determined.The truss anchor cable combined support design scheme is adopted for the west three middle roadway of Yong’an Coal Mine,and the monitoring data is ideal.The support design can control the deformation of the roadway well.