Characterization of fatigue resistance in welded joints for components of metallic bridges in the presence of construction anomalies

Abstract

We present the results of an experimental programme of fatigue tests carried out on two types of butt joints with thicknesses of 20 and 40 mm respectively, characterized by a significant gap between weld edges, not compliant with the requirements of construction specifications. The tests were conducted on specimens taken from the weld beads of joints typical of those produced at the site (butt joints between web and flanges) and made with the same procedures (welding process, welding position, welding filler, etc.). The test results were elaborated statistically to determine the fatigue resistance category in accordance with the requirements of standard EN 1993-1-9 and IIW recommendations. Calculations took into account both the thickness of the specimens (tests were carried out on both to-scale and true-thickness specimens for the purposes of validation) and also flexural stress components induced by the non-planarity of the specimens.

Keywords::

• bridges
• butt joints
• civil engineering
• fatigue loading
• fatigue strength
• fatigue tests
• fitness for purpose
• imperfect shape
• standards
• structural members
• structural steels
• test pieces
• welded joints

Notes

Paper presented at the ‘Gyrate Nazionali di Saldatura 6’ [National Welding Days] during the workshop ‘Structural reliability’ – Genoa 26-27 May 2011.

Additional information

Notes on contributors

M. Lanza

Michele Lanza, who was awarded a degree in Mechanical Engineering at the University of Genoa, has been working at the Italian Institute of Welding since 1981. He obtained the IWE qualification and has extensive experience in the Metalworking, Engineering and Laboratory Divisions (as Division Manager). He is currently employed by the company IIS SERVICE, where he was initially appointed as Manager of the Civil Structures Division. He has been Manager of the Engineering Division at this firm since 2012.

C. Servetto

Chiara Servetto was awarded a degree in Civil Engineering at the University of Genoa in 1992. She has been working at the Italian Institute of Welding since 1992. After gaining experience in the Laboratory and Engineering Division, she now works as a consultant for the company IIS Service and has been a Quality Assurance manager for the same firm since 2012.