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Experimental Research on Small Diameter Concrete-Filled Steel Tubular by Ultrasonic Detection

Ultrasonic testing technique is an important nondestructive testing method, which has been widely used to the defect detection of CFST and is the preferred alternative for concrete close-grained degree and uniformity test. The test becomes difficult when the diameter of the concrete-filled steel tubular is less than 250mm,as the combination of different media and the reduction of dimension on CFST increase the difficulty degree of detection. As the experimental research basis, 4 different preinstalled-defect CFST are produced. The principle and methodology of Ultrasonic detection is comprehensive researched on the signal characteristics, such as wave speed, wave amplitude, sound speed and wave shape, etc. It gives useful suggestions for the theory and practice of identification of defect types and the quality control in small diameter CFST.