ULTRASONIC TESTING ON THE LOAD MONITORING OF PRE-STRESSED CABLE AND ITS APPLICATION
锚索预应力声测技术研究及工程应用

In view of the insignificant change of ultrasonic velocity and amplitude of the concrete under low load, the ultrasonic weighted spectrum parameter obtained from wavelet treatment is taken as the intermediate index during load monitoring of pre-stressed cable. The rating curve of the weighted wave spectrum parameter and load on the concrete anchored pier during pretension of pre-stressed cable is standardized. Based on those standardized curves, the pre-stress of cable is calculated by the ultrasonic monitoring data of concrete anchored pier. The application result of this technology to a slope project shows that when load change exceeds 50 kN, the change of weighted wave spectrum parameter is obvious and this can reflect the change course of the loss of pre-stress. The ultrasonic testing results have a good agreement with load sensor results.