A RANDOM, NONDESTRUCTIV AND DYNAMIC TESTING APPARATUS AND METHOD OF THE STRESSED STATE OF A ROOF BOLT

摘要

A random, nondestructive and dynamic testing method of the stressed state of a roof bolt includes arranging an exciting force fixture (7) on external end of the roof bolt (1) which is anchored in the rock, and mounting an accelerometer (5) on a fixing nut (6) of the external end of the roof bolt (1), connecting an intelligent and dynamic collecting tester (8) to the accelerometer (5), applying a force to the exciting force fixture (7) and making the roof bolt vibrate transversely, collecting accelerating signals of the vibration by the accelerometer (5) and transmitting to the intelligent and dynamic tester (8), transferring the received accelerating analog signals to digital signals and storing by the intelligent and dynamic tester (8), inputting the data finally to a computer and processing, then the pre-stress testing when the roof bolt is initially installed and the load testing of working state are accomplished.