喷锚支护中的承压拱理论及实验研究

Theory for Pressure Bearing Arch in Lock Bolt Support and Its Experiment Study

根据喷锚支护加固机理,从理论上阐述了系统布置全长胶结式锚杆时,由于锚杆和喷射混凝土与围岩的共同作用,在锚杆互相作用影响范围之内会形成一个加固后的承压拱。经过实验室和现场实验,得出了承压拱的厚度与锚杆的长度、间距、围岩的力学性质等因素有关。对实验数据和结果的处理与分析,给出了单根锚杆加固影响范围系数K以及根据围岩所需承压拱最小厚度、锚杆加固影响范围系数Kl和锚杆的间距来确定锚杆长度的方法。

In line with mechanism of lock bolt support and from theory, the paper expounds that when anchor rods are arranged binding in its whole length, a pressure bearing arch after reinforcement will be formed within influence scope of the rods interaction owing to joint action of rod, shotcrete and surrounding rock. Through lab and field experiments, it has drawn that the thickness of pressure bearing arch is related to the rod length, interspace between the rods and mechanics nature of surrounding roek etc. Treatment and analysis of experiment data and results have given the coefficient K for reinforcement influence scope by single rod and the methods determining the rod length according to minimum thickness of pressure bearing arch, which is required by surrounding rock, coefficient K1 for reinforcement influence scope by the rod as well as interspace between the rods.