针对煤矿锚杆支护的特点,首先从理论上研究应力波在托板处、锚固开始位置、锚固结束位置的反射和透射规律;然后模拟纵波在全长锚固锚杆内传播速度与树脂一围岩粘结刚度之间的关系;最后在锚杆支护实验室进行了预应力锚杆支护实测对比试验。研究结果表明,应力波反射法不仅可以检测锚杆的锚固位置和锚固长度,而且能由锚固体波速间接检测锚杆的锚固力大小。
In view of the characteristics of bolt supporting in mine, the reflection and transmission law of stress wave at the initial anchorage position, terminal anchorage position and splint are investigated in theory. Secondly, the relation between longitudinal wave propagation velocity and resin-bonded stiffness of full length anchoring bolt is simulated. Finally, comparative tests for anchoring quality of anchor cables are conducted in bolt supporting laboratory. Research shows that stress wave reflection method can not only detect the anchoring position and anchoring length, but also indirectly detect the bolt anchoring force through anchor wave velocity.