Estimates of regions of stress concentrations in ‘t’ butt weld geometries

Abstract

Values of the surface and the die away distance to unity of stress concentration factor have been found on typical geometries of ‘T’ butt and cruciform joints using finite elements. Results show that within the range of geometric variables studies and within the uncertainties of the secondary variables (e.g., mesh pattern) the term that dominates both value and extent of stress concentration for tensile loading is the ratio of weld leg length to the size of the continuous member. It is also argued that simplified estimation schemes, such as linearization of the peak local stress bounded at unity, need not be conservative with large margins on both the peak value and the extent over which it operates.

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