Nondestructive Evaluation for Bottom Edges of a Rail using Guided Waves
The use of ultrasonic wave technology has been anticipated as an important technology in inspection and health monitoring of rails. Currently rail inspection cars and rail inspection tools equipped with special transducers such as wheel probes has been feasible in inspection of a railhead and a web. However, the bottom edges of rail, easily damaged regions due to contact to soil and fastening, are blind zones for such conventional ultrasonic inspection technique in which signals are input from a railhead, and the defects in bottom edges of rails can not be detected. Therefore, in this paper, inspection technique for defects in bottom edges of rails is discussed by using guided waves. Dispersion curves in a rail were numerically elucidated by a semi analytical finite element method. Furthermore, the suitable modes to inspection for bottom edges were selected by deriving dispersion curves and wave structures. Particularly ,among a thousand of propagating modes, a Ray leigh mode propagating on side surfaces of the bottom edges was found out to be the best mode for a rail with fastenings. And an inspection tool was designed and developed for generating and receiving the Ray leigh mode, and satisfactory defect echoes were obtained with fastenings.
超声检测 色散曲线 传播模式 检测盲区
Chang Jun-Jie
Japan Probe Co., Ltd, Yokohama, 232-0033, Japan
国内会议
厦门
英文
137-143
2011-11-11（万方平台首次上网日期，不代表论文的发表时间）