1. Overview of Investigation to Understand Progression of Concrete Tie Conditions in High Speed Applications Jeff Henderson Project Engineer Prepared for the International Concrete Crosstie and Fastening System Symposium June 2012

2. Project Team o FRA Office of Research and Development o AMTRAK o ENSCO FRA OR&D Funded under BAA-2010-1 Sponsored by the Federal Railroad Administration

3. Research Objectives Develop a better understanding of the progression of defects in concrete ties over time Advance the use of machine vision technology in concrete tie inspection Improve concrete tie inspection practices for high-speed applications

4. Focus of Study Determine progression rate of cracks in concrete crossties Enlargement Consider a statistically significant sample size (~250,000 ties) Employ three measurement surveys spanning 1.5 years

5. Motivation for Study Hairline cracks ultimately result in tie failures upon reaching the rail seat Intended Broader Impact More efficient inspection intervals Improved maintenance planning and budgeting Improved safety and net operating efficiency

6. Main Technical Objective Better understand the progression from “A” to “B” B A Hairline End Crack Tie Failure

7. High-level Approach Assess progression of tie condition at discrete states Combine results to paint a more continuous picture EarlyMidLate

8. Methodology Crack progression assessed “virtually” rather than “live” Machine vision will be used to help locate cracks Crack measurements will be made manually Test Equipment Track Bed Imaging System Rail Side View Imaging System Track Bed Imaging Rail Side View Imaging Implementation Plan Overview

9. Test Zone 1 High Street to Atwells Start/End MP: 143 – 184 Tie Installation Dates o Brand new o 1978-1979 San-Vel o 1993-1994 Rocla Traffic: Passenger & Freight o Passenger tonnage: 4.7 to 4.9 MGT o Freight tonnage: 0.1 to 1.5 MGT Track Miles: 82 miles

10. Test Zone 2 Hebronville to Mansfield Start/End MP: 193 – 204 Tie Installation Date: 1979 San-Vel Traffic: Passenger & Freight o Passenger tonnage: 4.7 to 4.9 MGT o Freight tonnage: 0.6 to 0.8 MGT Track Miles: 22 miles

11. Technical Challenges Challenge 1: Locating hairline cracks in a set of ~250,000 concrete ties Challenge 2: Precisely aligning ties between consecutive runs “Enlarge the needle”“Get your ducks ties in a row”

12. Main objective of project: To better understand the progression of cracks in concrete ties Final report to discuss: –Improved concrete tie inspection practices and intervals –Approaches for improving the reliability of concrete tie inspections –Approaches for improving tie inspection efficiency –Approaches for reducing concrete tie inspection cost Summary

13. Acknowledgements FRA Office of Research and Development: Mr. Hugh Thompson, FRA COTR Amtrak Mr. Joe Smak Mr. Michael Trosino Mr. Steven Sawadisavi Thank you