Experimental Techniques

, Volume 40, Issue 4, pp 1179–1185 | Cite as

In Situ Monitoring of Rail Squats in Three Dimensions Using Ultrasonic Technique

  • S. Kaewunruen
  • M. Ishida


Rail squats and studs are typically classified as the growth of any cracks that have grown longitudinally through the subsurface of rails. This study highlights in situ monitoring of squat/stud distribution and its growth in the field. Squat/stud growth has been determined and plotted using the ultrasonic measurement device and the crack depths at each reference grid node form a three-dimensional contour of rail squat crack. In this study, the crack propagation of squats/studs is roughly estimated to be almost linear to repeated train loads called as accumulated passing tonnages up to a certain degree of propagated crack length. This in situ monitoring is of significance to railway authorities in order to effectively and efficiently prioritize maintenance functions, which will improve safety and reliability of the rail network.


Rail Surface Defect Squats and Studs Ultrasonic Mapping Field Monitoring Asset Management 


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Copyright information

© The Society for Experimental Mechanics, Inc 2016

Authors and Affiliations

  1. 1.Birmingham Centre for Railway Research and Education, School of Civil EngineeringThe University of BirminghamBirminghamUK
  2. 2.Railway Engineering Department, Railway DivisionNippon Koei Co. Ltd.TokyoJapan

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