Residual Stresses in Rectangular Plates with Slit-type Butt Welded Joint
A Theoretical Study of Residual Welding Stresses and Deformations (Report 2)
1971 Volume 40 Issue 5 Pages 459-473
Details
1971 Volume 40 Issue 5 Pages 459-473
As an example of the applications of theoretical analysis of residual welding stresses based on the inherent strain, stress distributions in finite rectangular plates with slit-type butt welded joint are presented and compared with experimental results. In this report, the inherent strain distributions along welded joint are mathematically expressed by superposition of the basic functions which depend only upon the distance from an arbitrary point on the welded line. Residual stresses are calculated by applying the inherent stress theory developed in the first report by the author.
The basic function is obtained as a solution of the Abel's integral equation for the distribution of inherent longitudinal strain in simple butt welded joint. The longitudinal and transverse components of inherent strain are determined by the superposition of the same basic functions, where the density of distribution is assumed to be uniform along welded joint for the longitudinal strain and convex for the transverse strain. The density of inherent transverse strain is determined by trial and error method such that the measured transverse shrinkage along welded joint may coincide with the inherent transverse shrinkage calculated from the inherent transverse strain supposed above. The magnitude of inherent longitudinal strain is determined on the assumption that the residual longitudinal stresses at midlength of joint are equal to the yield stress of weld metal, the value of which is presented in the first report as the result of elastoplastic analysis of welding stresses in simple butt joint.
The numerical calculation is carried out by means of Fourier seriers., This procedure is a systematic treatment of rectangular plate problems. Figures 4 to 6 show the results of the calculated residual welding stresses in rectangular plates for various slit lengths. The experimental results are also plotted.
