Investigation and Application On Monitoring the Compactness of Concrete-Filled Steel Tube Structures With Ultrasonic Wave

Five full-scale specimens of the Ganhaizi long-span bridge, which is concrete-filled steel tube (CFST) truss structure, were fabricated to simulate the potential defects, such as debonding, void, mortar, etc. The specimens were tested using the ultrasonic wave based method. The relevant regularity and evaluation standards for identification of defects were obtained from the test results. The ultrasonic wave based method was also applied to Ganhaizi long-span bridge for checking the pouring quality of CFST structure. The measured data not only demonstrated the accuracy of the relevant evaluation standards, but also proved that the ultrasonic wave based method researched in this paper is an effective method to detect the compactness of CFST structures.