High Speed Rail IDEA Project 41 [Completed (IDEA)]
Reliability of Improved Thermite Welds
Project Data
Funds:
$38,832
Staff Responsibility:
Chuck Taylor
Completion Date:
9/1/2004
Fiscal Year:
2003
This IDEA program study (HSR-41) confirms the results of its prior IDEA program study (HSR-24) that thermite-weld fatigue resistance can be significantly and reliably increased by improving the shape of the weld-toe in the web-base fillet and rail-base regions of the weld and by suppressing common weld-toe defects found there. Laboratory 4-point bending fatigue tests were carried out on five series of thermite welds:three series had a standard external shape currently in use and two series had an improved shape developed in this study. Test laboratory results show that improved welds have a fatigue life approximately 2 times that of standard welds.
Twenty-one (21) welds with the improved shape were installed in the TTCI FAST track facility in PuebloColorado.Several of the 21 welds failed prematurely; and thus, all of the remaining 21 were removed from the track.A small fabrication fault in the web of the improved welds was identified and has been corrected, new molds are being manufactured and a second series of improved welds will be installed in the FAST track
At the conclusion of the project recommendations were developed to alter the equipment, materials, and techniques used by track maintenance personnel when they perform thermite welding in the field.
The final report for this IDEA project can be found at:
