Speakers

View Full Calendar

William W. Hay Seminar: Title: Assessment of Rail Track Condition Using Novel Nondestructive Evaluation Technologies

Event Type
Seminar/Symposium
Sponsor
Rail Transportation and Engineering Center (RailTEC)
Virtual
wifi event
Date
Feb 5, 2021   12:30 pm  
Speaker
John S. Popovics | University of Illinois Urbana-Champaign
Cost
No Charge for Non-PDH | $25 for PDHs
Registration
Registration
Contact
Emma J Ehrenhart
E-Mail
hayseminar@illinois.edu
Phone
217-300-1340
Views
35
Originating Calendar
William W. Hay Railroad Engineering Seminar

Abstract  
Recently developed nondestructive evaluation (NDE) technologies provide opportunities for more sensitive and effective evaluation of track structure condition. Here I present recent work from my research group to develop and apply new NDE technology for two different track condition issues. First, I describe contactless non-destructive evaluation technology for fast and continuous condition assessment of concrete railroad ties. Ultrasonic surface waves are generated in railroad ties using an air-coupled ultrasonic transmitter and receiver set, where concrete railroad ties with different types of damage are evaluated. A set of signal parameters are used to generate two- and four-dimensional decision spaces computed using the support vector machine (SVM) algorithm. The results demonstrate that high quality signal data are obtained, and specific decision spaced can identify healthy and damaged railroad ties with an accuracy of around 80%. Next, I describe in-progress work to evaluate the use of impulse vibration test data collected from continuous welded rail (CWR) to monitor stress state in the rail. In this study, vibration data are collected from an instrumented section on a revenue-service rail line, where true axial stress state and temperature are continuously monitored over the long term. Resonant vibration data are collected across different temperatures and stress states demonstrate that certain high-frequency modes of vibration are affected in different ways by temperature-induced thermal stress in the rail. Signal processing algorithms that identify, extract, and monitor pertinent vibrational modes within the rich experimental vibration spectra are described, and identifiable temperature and stress-induced behaviors are discussed. Approaches to invert the collected data to predict rail stress state are discussed.

Speaker
John S. Popovics is Professor, Associate Head, and Director of Undergraduate Studies for the department of Civil and Environmental Engineering at the University of Illinois. His primary research interests are non-destructive evaluation, imaging and sensing to assess the condition of infrastructure materials and structures. His research findings have been published in five chapters in books and eighty-five articles in refereed technical journals. He received the NSF CAREER award in 1999, the ASNT Fellowship Award in 2012, and the ASNT Faculty Award in 2014. He has been recognized as a Fellow of the American Concrete Institute (ACI) and the American Society for Nondestructive Testing (ASNT), and he is a registered professional engineer in the Commonwealth of Pennsylvania.

link for robots only