LONGITUDINAL STRESS (FORCE) MEASUREMENT OF RAIL UNDER OPERATING CONDITIONS

Award Information
Agency: Department of Transportation
Branch: N/A
Contract: N/A
Agency Tracking Number: 1839
Amount: $265,705.00
Phase: Phase II
Program: SBIR
Awards Year: 1986
Solicitation Year: N/A
Solicitation Topic Code: N/A
Solicitation Number: N/A
Small Business Information
Magnasonics Inc.
215 Sierra Drive Se, Albuquerque, NM, 87108
DUNS: N/A
HUBZone Owned: N
Woman Owned: N
Socially and Economically Disadvantaged: N
Principal Investigator
 Dr. George A. Alers
 Investigator
 () -
Business Contact
 DR. GEORGE A. ALERS
Title: PRESIDENT
Phone: () -
Research Institution
N/A
Abstract
IN 1982, A SPECIAL COMMITTEE OF THE NMAB ISSUED A REPORT ON THE NONDESTRUCTIVE METHODS THAT MIGHT BE USED TO MEASURE THELOGITUDINAL FORCE IN INSTALLED RAILS. IT SHOWED THAT THE ACOUSTO-ELASTIC EFFECT WHICH INFERS THE STRESS FROM MEASURE MENTS OF SMALL SHIFTS IN THE VELOCITY OF SOUND WAS PROMISINGBUT DIFFICULT TO IMPLEMENT BECAUSE VARIATIONS IN THE METALLURGICAL STRUCTURE OF THE METAL AND UNCERTAINTIES IN THE COUPLING BETWEEN THE RAIL AND THE TRANSDUCER APPEAR TO CAUSE VELOCITY SHIFTS THAT MASK THE DESIRED MEASUREMENTS. THIS PROPOSAL AVOIDS THE COUPLING PROBLEM BY USING COUPLANT-FREE EMATS AND IT MINIMIZES THE ROLE PLAYED BY METALLURGICALTEXTURE BY USING A NEWLY DISCOVERED ACOUSTO-ELASTIC EFFECT THAT IS BASED ON THE SYMMETRY PROPERTIES OF THE STRESS TENS TENSOR RATHER THAN THE VALUES OF ANY METALLURGICAL CONSTANTS. THE PROPOSED PHASE I EFFORT IS INTENDED TO DEMONSTRATE THEFEASIBILITY OF DEDUCING THE LOGITUDINAL STRESS LEVEL FROM A PORTABLE PROBE HELD AGAINST THE WEB OF THE RAIL.

* information listed above is at the time of submission.

Agency Micro-sites

SBA logo
Department of Agriculture logo
Department of Commerce logo
Department of Defense logo
Department of Education logo
Department of Energy logo
Department of Health and Human Services logo
Department of Homeland Security logo
Department of Transportation logo
Environmental Protection Agency logo
National Aeronautics and Space Administration logo
National Science Foundation logo
US Flag An Official Website of the United States Government