Concrete Inspection Signal Pre-processing Method Based On TFM Imaging.

The concrete structure contains a large amount of gravel, aggregate and steel bars, which form a variety of acoustic interfaces. The signal components in the concrete structure are complex, and the ultrasonic energy is easily attenuated. Ultrasonic testing for concrete structure has always been a research hotspot. In order to improve the concrete detection resolution and signal-to-noise ratio, a concrete ultrasonic array detection method based on the total focusing method is proposed. At first, the concrete ultrasonic array simulation study is carried out through the establishment of a concrete finite element model, and the array probes are stimulated sequentially by simulating a excitation and multi-receiving method, and the detection signal is obtained; Then full matrix capture is obtained after convoluted filtering, waveform envelope analysis and signal sharpening processing which would avoid errors caused by noise and phase; Finally, the full matrix capture is processed and imaged according to the total focusing method to display the model detection results. The simulation experiment results show that the proposed imaging algorithm can achieve higher resolution and signal-to-noise ratio compared with the synthetic aperture focusing algorithm.