巷道底角锚杆控制底鼓机理及选型试验

煤矿开采进入深部以后,地质力学环境远比浅部复杂,各种非线性大变形力学现象越来越显著,巷道底鼓问题也更加突出。为探究控制巷道底鼓效果最好的锚杆类型,首先根据锚杆控制巷道底鼓力学分析模型,从有效切断底板塑性滑移线和有效分解力的作用两方面,对底角锚杆控制底鼓的作用机理进行力学分析;然后进行室内试验,加工6种不同材质及规格的底角锚杆,进行抗弯力学性能试验,通过对试验结果进行优化分析,最终确定控制巷道底鼓最适宜的底角锚杆类型,即I-3型底角锚杆;并将此类锚杆成功应用于大屯孔庄矿-785轨道大巷工程。监测结果表明,此类控制巷道底鼓锚杆在实际工程中取得明显的技术效果。

Research on mechanism for floor heave control in the roadway by base-angel-bolt and its type selection test

The geological and mechanical conditions of roadways become more complicated compared with those in the shallow part with the mining depth increasing. Consequently, the nonlinear mechanical phenomena especially the problem of floor heave in the roadway occur frequently. In order to explore the most effective type of cable fixed in floor, at first, the mechanism of floor heave controlled by the base-angle-bolt has been analyzed in two ways including cutting off plastic slip line effectively and de-composing pressure according to the mechanical analytical model of the bolt controlling roadway floor heave. Then six types of base-angel-bolt with different materials and specifications have been designed to carry out bending test. According to the optimized analysis of the results, the most appropriate type of I-3 has been determined and successfully applied in the engineering practice of Kongzhuang -785 mine in Datun. And the displacement monitoring curve has indicated that an obvious effectiveness has been obtained by applying the type of I-3 base-angle-bolt.