巷道锚杆支护特性分析与应用

Analysis and application on bolt support characteristic of roadway

对采用锚杆工作阻力为夹紧力、锚固区围岩力学性质不改变的计算方法得出的结果进行了分析,研究了巷道锚杆支护作用的特性及其相关因素间的影响关系.结果表明:锚杆巷道围岩径向、切向应力在锚杆锚固端位置有一个跳跃;锚杆长度一定时,支护强度对围岩塑性区半径、巷道位移的影响随锚杆工作阻力值的提高逐渐减弱;锚杆工作阻力强度一定时,锚杆支护巷道周边位移、围岩应变软化区半径及破碎区半径,随锚固区半径增加开始阶段显著减小,基本呈双曲线函数关系,一定阶段后,变化趋缓,呈近水平直线变化.并在程村矿井下巷道进行了一次锚杆支护的设计应用.

Analysed the calculation result obtained in a manner that bolt work resistance is clamping force, and surrounding rock mechanics character of anchor district does not change. Support characteristic of the bolt roadway, and influence relationships of correlative factors were researched. The results indicate that surrounding rock radial stress and circumferential stress have a jump on anchor place of bolt inner end; the change values of surrounding rock plastic district radius, and roadway perimeter displacement are gradually decrescent with support strength increasing when bolt length is fixed ; the plastic district radius of surrounding rock, brocken district radius, and roadway perimeter displacement remarkablely decrease in initial stage with anchor district radius increasing when bolt support strength is fixed, the relationship of which are basically function of hyperbolic curve , after a certain stage, their changes gradually moderate that the relationship curves are approximately horizontal line in the main. And finally, the trial for bolt design of the first support was performed in Chengcun Mine＇ s roadway.