Application of Ultrasonic Testing in Concrete Filled Steel Tubular Arch Bridge

Abstract

Concrete Filled Steel Tube(CFST) is widely used in civil engineering structures because of its superior mechanical performance. Yet the mechanical behavior of CFST is highly depended on the construction quality of the filled concrete. Hence it is very important for the inspection of the construction quality of the filled concrete in CFST structures. In this paper, the ultrasonic testing technique was used to detect the defect of the filled concrete of a CFST arch bridge. During the inspection, the ultrasonic transducer was moved along the circumference of the cross-section of the arch, and the defect of the concrete was comprehensively judged by detecting the change of sonic time, sonic amplitude and sonic frequency. Based on the analysis of the ultrasonic transmission path, the influences of different defects on the sonic time, sonic amplitude and sonic frequency were discussed. The detecting results were verified by core-drilling method. The verification showed that different kinds of defects defected by ultrasonic testing was in good accordance with the drilling samples, which demonstrates the adaptability of the ultrasonic detection technique in the construction quality inspection of CFST structures.