Upload
johnathan-heath
View
213
Download
0
Embed Size (px)
Citation preview
Overview of Investigation to Understand Progression of
Concrete Tie Conditions in High Speed Applications
Jeff HendersonProject Engineer
Prepared for theInternational Concrete Crosstie and Fastening System Symposium
June 2012
Project Team
o FRA Office of Research and Development
o AMTRAKo ENSCO
FRAOR&D
Funded under BAA-2010-1 Sponsored by the Federal Railroad Administration
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
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
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
Main Technical Objective
Better understand the progression from “A” to “B”
BA
Hairline End Crack Tie Failure
High-level Approach• Assess progression of tie condition at discrete states• Combine results to paint a more continuous picture
Early Mid Late
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
Test Zone 1
High Street to Atwells• Start/End MP: 143 – 184
• Tie Installation Dateso Brand newo 1978-1979 San-Velo 1993-1994 Rocla
• Traffic: Passenger & Freighto Passenger tonnage: 4.7 to 4.9 MGT o Freight tonnage: 0.1 to 1.5 MGT
• Track Miles: 82 miles
Test Zone 2
Hebronville to Mansfield• Start/End MP: 193 – 204
• Tie Installation Date: 1979 San-Vel
• Traffic: Passenger & Freighto Passenger tonnage: 4.7 to 4.9 MGT o Freight tonnage: 0.6 to 0.8 MGT
• Track Miles: 22 miles
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”
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
AcknowledgementsFRA Office of Research and Development:
• Mr. Hugh Thompson, FRA COTR
Amtrak
• Mr. Joe Smak
• Mr. Michael Trosino
• Mr. Steven Sawadisavi
Thank you