Research On Rail Defect Detection Method Based On Ultrasonic Phased Array Low Rank Matrix Recovery

With the rapid development of urban rail transit in my country,as of the end of2020,the total mileage of high-speed rail has been close to 40,000 kilometers.It is expected that the total mileage of high-speed rail will further increase to 70,000 kilometers from 2020 to 2035.Rails will inevitably produce wear and defects during use,so non-destructive testing techniques are needed to evaluate the quality of the rails.However,if the track base is huge,corresponding requirements are put forward for the accuracy and rapidity of non-destructive testing technology.Ultrasonic phased array nondestructive testing methods are gradually replacing traditional conventional ultrasonic testing because they can achieve the characteristics of deflectable and focused sound beam without moving the probe.Based on the ultrasonic phased array nondestructive testing method,this paper describes the current research status of ultrasonic phased array nondestructive testing methods at home and abroad,and explains the principle of ultrasonic phased array rail defect detection.This paper proposes a rail defect detection method based on ultrasonic phased array low-rank matrix recovery.The sampling time of the front-end probe of ultrasonic phased array is shortened,and the method of back-end data low-rank matrix recovery effectively reduces the amount of data collected Ultrasonic phased array rail defect detection rate.The main research contents of this paper are as follows:(1)Based on the mathematical formula calculation of the ultrasonic phased array sound beam deflection delay law and the focus delay law,how to control the ultrasonic phased array sound beam to propagate through the ultrasonic phased array wedge in the steel rail for deflection and focusing is studied.The sound field in the steel rail was simulated to verify the effect of sound beam deflection and focusing.CIVA simulation is carried out for the detection of defects in the rail,which verifies the detectability of the rail defects by the ultrasonic phased array.(2)Researched and analyzed the reasons for the limitation of ultrasonic phased array rail defect detection rate,proposed a physical front-end probe to reduce the sampling back-end data to perform low-rank matrix restoration of the rail detection method,and designed ultrasonic phased array rail defect detection based on low-rank matrix restoration.The system realizes the function of this method.(3)The ultrasonic phased-array rail defect detection system based on sparse matrix recovery has been experimentally verified on the B-type portable phased-array test block and the standard damaged rail.The defect can be realized under the method of differential sampling of the corresponding ultrasonic phased-array probe.The detection and corresponding physical information analysis.