The federal highway administration investigated the fatigue characteristics of thermex steel (it has different physical propeties from conventional reinforcing steel containing alloying elements) versus conventional reinforcing steel before its large scale use could be perimtted. Details of the investigation are reported in this article. The background to the study is described. The specimens are described, as well as fatigue testing, and gripping methods. The findings are presented and discussed. A large scale discrepancy was noted between the test results and the british standard. The research developed insufficient data to make any conclusions regarding the relative fatigue resistance of the bars produced by the thermex process. A need was indicated for the development of a u.S. Specification for testing reinforcement bars.
Abstract