Fatigue design of welded aluminum rectangular hollow section joints

Norwegian University of Science and Technology, Department of Structural Engineering, Rich. Birkelandsvei 1a, N-7034 Trondheim, Norway
Engineering Failure Analysis (Impact Factor: 1.13). 01/1999; DOI: 10.1016/S1350-6307(98)00025-9

ABSTRACT Fatigue design methods for welded aluminum joints are reviewed, including various approaches to fatigue life estimation currently adopted in design codes across a range of industrial applications. The applicability of these established methodologies to the fatigue design of automotive space frame structures is critically assessed. The hot spot stress method is identified as the most promising in terms of providing a coherent and comprehensive approach to design. Particular problems related to implementation are considered such as failure sites and determination of appropriate stress concentration factors from physical models, finite element calculations or parametric equations. Preliminary results from finite element stress analyses and fatigue tests are also presented for rectangular hollow sections welded in a T-joint configuration. Recommendations are made for a design methodology for welded rectangular hollow-section joints in aluminum space frames, including use of a single hot spot S–N curve.

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