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Air-Borne Tie Sonar for Loaded Tie Deflection Measurements

Document Series
Research Results
Report Number
RR 22-14
Subject Track
Non-destructive evaluation, ultrasonic inspection, railroad tie deflection, non-contact inspection, ultrasonic ranging, center-binding, track

This report presents a non-contact ultrasonic technique to map the full-field surface deflection of railroad ties using known concepts of sonar-based distance measurements. Between September 2019 and July 2021, the University of California San Diego (UCSD) created a beam with six sonar sensors and performed field testing at the UCSD Rail Defect Testing Facility (RDTF) and at a Burlington Northern Santa Fe (BNSF) rail yard in San Diego, CA. The test results indicate the potential of this non-contact system to measure full-field tie deflections in three-dimensions (3D) and possibly detect defective tie-ballast support conditions such as center-binding.

Last updated: Friday, August 12, 2022