01373760

Component

Nondestructive impact velocity measurements are used to document the current condition and integrity of concrete cross ties and provide intrinsic information that can be used to classify concrete cross ties into three categories: 1) functional 2) marginally functional 3) non- functional. These results can be used to document the condition of each tie and identify ties for immediate replacement, future monitoring (retesting at a later date) or no immediate action. Ties that are “good” (no immediate action required) have compressional wave velocity values greater than 14,000 ft/sec and shear wave velocity values greater than 7,000 + ft/sec. Ties classified as Marginally Functional, some cracking and delamination but not deteriorated to the point that they should be immediately replaced, have compressional wave velocity values of 13,000 to 14,000 ft/sec and shear wave velocity values in a range of 6,000 to 7,000 ft/sec. Ties that are classified as non-functional (deteriorated, cracked, delaminated and should be replaced) have compressional wave velocity values less than 13,000 ft/sec and shear wave velocity values either absent or less than 6,000 ft/sec. Based on these results, NDT Corporation developed an automated data acquisition system that rolls along the track testing a tie every second or approximately 1 mile of ties per hour. The system has been fitted to a light weight Nolan Cart so that it can be easily moved along the rails and moved off of the rails to allow traffic to pass.

This paper was sponsored by TRB committee AR060 Railway Maintenance

01362476

12-1087

English

9p

2012

Transportation Research Board 91st Annual Meeting

Digital/other

Photos

Concrete ties; Condition surveys; Data collection; Maintenance of way; Nondestructive tests; Railroad ties

Maintenance and Preservation; Railroads; I61: Equipment and Maintenance Methods

Transportation Research Board Annual Meeting 2012 Paper #12-1087

TRIS, TRB

Feb 8 2012 4:59PM