Concrete Structure's Ultrasonic Testing Simulation And Processing

The research in this paper is supported by the NSFC's(National Natural Science Foundation of China's) Funding: Smart Concrete and its Structure.(Program No:50238040.)At the beginning of this paper, using the finite element simulation software to simulate the ultrasonic signal transmission in the different concrete structure. The first arrival time of signal containing noise can be accurately detected by using modulus maximum method. The programming has realized the curving ray tracing method based on the Snell law. Later, the first-arrival traveling time is used as the original projection data in 2D ultrasound CT imaging reconstruction. The main tasks of this paper are listed below.1. Abstained a series of the wave map by using the finite element simulation software ANSYS to simulate the ultrasonic signal transmission in the different concrete structure.2. Established the method of extracting first arrival time from the ultrasonic signal in the process of CT inversion. The method is higher accuracy and stronger anti-noise than conventional method.3. Realized the curving ray tracing method based on the Snell law. The results show a much better accuracy than the linear model and closer to the reality.4. Using the first-arrival traveling time abstained by experiment and simulation as original projection data in ultrasound CT reconstruction, reconstructed by SVD method and OLSON company's software.The fruits achieved in this paper will make ultrasonic CT testing have better application in Concrete's NDT and have certain significance to guide's development. Authors deeply believe that ultrasonic computerized tomography technique will have vast prospect in application.