多裂隙围岩中锚固结构形成的力学机理

Mechanical mechanism of bolted structure forming in strong fissured surrounding rock

把顶板锚固结构简化为均布荷载作用下两端固定支撑的梁,通过分析该固定支撑梁的力学平衡条件,确定了形成锚固结构所需锚杆预紧力与巷道顶压集度、顶板岩石物理力学参数、锚杆有效长度、布置间距之间的定量关系;把两帮锚固结构看作顶板锚固结构的支撑体,通过分析锚固结构的支撑能力与侧向压力的关系,建立了巷道两帮形成锚固结构所需锚杆预紧力与巷道顶压集度、两帮岩石的力学参数、锚杆有效长度、安装根数之间的定量关系。研究结论在大同矿区15号煤层巷道支护中得到应用,效果良好。

Simplified roof bolted structure as a built-in beam acted by uniformly distributed load,the relationship between roof bolt pretension force and some factors was determined by analyzing the balance of the built-in beam,the pretension force was needed by roof bolted structure forming and the above factors include roadway roof pressure,physical property or mechanical property parameters of roof rock,effective length of bolt and bolt separation.Regarded side bolted structure as a body supporting roof bolted structure,the relationship between side bolt pretension force and some factors was determined by analyzing the relationship between confining stress and supporting ability of the supporting body,the side bolt pretension force was needed by side bolted structure forming and the factors above include roadway roof pressure,mechanical parameters of side rock,effective length of side bolt and the side bolt separation.The conclusion obtained was used when roadway support system was designed in No.15 seam of Datong mining area and achieved good result.