Technical Reports

Laboratory Fatigue Testing of Selected Welded and Bolted Aluminum Connections for Freight Car Design

  • 01
  • Jun
  • 1993
AUTHOR: W. H. Walker, F. V. Lawrence Jr., V. Sharma
SUBJECT: Rail and Infrastructure Integrity
KEYWORDS: Fatigue Properties, S-N Diagram, Modified Goodman Diagram
ABSTRACT: This report describes the tests conducted to determine the fatigue properties of joints and construction details in aluminum-bodied freight cars. The tests were conducted at the Department of Civil Engineering of the University of Illinois at Urbana-Champaign. The funding for this test program was provided by the Association of American Railroads and the Federal Railroad Administration. Technical guidance was provided by the Freight Car Structures Fatigue Task Force. With the growing use of aluminum in lightweight freight cars, the importance of designing cars against premature failure from fatigue can hardly be overstated. Fatigue failures can occur at inadequately designed construction details. Eleven joint and details were selected for this test program, based on a survey of the needs of the industry. These joints and details were built using 5083 and 5086 aluminum alloys for sheets and 6061 series for extrusions. These are the commonly used aluminum alloys in freight car construction. The test specimen were fabricated by the freight car builders to ensure that the specimens reflected the fabricating and welding techniques used in actual construction. The data obtained through this test program will augment that available in the AAR Mechanical Division’s "Specification for Design and Construction of Freight Cars"(M-1001).