Rail Diagnostics Based on Ultrasonic Guided Waves: An Overview

Abstract

Rail tracks undergo massive stresses that can affect their structural integrity and produce rail breakage. The last phenomenon represents a serious concern for railway management authorities, since it may cause derailments and, consequently, losses of rolling stock material and lives. Therefore, the activities of track maintenance and inspection are of paramount importance. In recent years, the use of various technologies for monitoring rails and the detection of their defects has been investigated; however, despite the important progresses in this field, substantial research efforts are still required to achieve higher scanning speeds and improve the reliability of diagnostic procedures. It is expected that, in the near future, an important role in track maintenance and inspection will be played by the ultrasonic guided wave technology. In this manuscript, its use in rail track monitoring is investigated in detail; moreover, both of the main strategies investigated in the technical literature are taken into consideration. The first strategy consists of the installation of the monitoring instrumentation on board a moving test vehicle that scans the track below while running. The second strategy, instead, is based on distributing the instrumentation throughout the entire rail network, so that continuous monitoring in quasi-real-time can be obtained. In our analysis of the proposed solutions, the prototypes and the employed methods are described.

Monitoring System for Railway Infrastructure Elements Based on Thermal Imaging Analysis

“…A rail defect detection system consists not only of an instrumented vehicle with a set of sensors but also a data acquisition system, a data analysis tool, and data processing algorithms. Railway track inspection uses non-destructive techniques [ 15 , 16 ] which can be divided into vision-based methods such as laser scanners [ 17 ] and video image processing [ 18 ], as well as displacement-based methods such as acceleration measurement [ 19 ], which measure the vertical movement of vehicles to detect damage to rails and other track components. Thermal imaging cameras are also of great importance in diagnosing rail defects.…”

Special Issue on Novel Approaches for Structural Health Monitoring

“…The diagnostic of rail tracks damage conditions is the topic investigated in [3]. The authors give an extensive overview from the general context to the latest innovations, focusing on different non-destructive testing (NDT) methodologies.…”

Diffuse Ultrasonic Wave-Based Damage Detection of Railway Tracks Using PZT/FBG Hybrid Sensing System

“…Ultrasonic guided wave method adopts an active manner to monitor structural conditions, which makes this method immune to most noise in condition monitoring of the railway system [ 12 , 13 , 14 , 15 , 16 ]. The ultrasonic guided wave is excited at a well-selected frequency and interacts with the defects.…”