PSI - Issue 13

Evy Van Puymbroeck et al. / Procedia Structural Integrity 13 (2018) 920–925 Evy Van Puymbroeck et al./ Structural Integrity Procedia 00 (2018) 000 – 000

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7.3. Welding speed The residual stress results for three different welding speeds are shown in Graph 3.

Graph 3.Transverse residual stresses with variation of welding speed.

The variations of the welding speed results in a large difference of the residual stresses. Lowering the welding speed results in a larger tensile yield stress zone and larger tensile and compressive residual stresses. The highest welding speeds gives the smallest tensile yield zone and smallest compressive and tensile residual stresses. Thus, increasing the welding speed will be beneficial in order to reduce the residual stresses.

8. Conclusions

To determine the residual stress distribution caused by welding the longitudinal stiffener to the bridge deck plate, a finite element model was set up. The transverse residual stresses on top of the deck plate are determined for a reference model with tack welds of 25 mm length, a welding current of 780 A and a welding speed 15.83 mm/s. The influence of a variation of these parameters was studied. The size of the tack welds has no influence on the residual stresses. A higher welding current and higher welding speed results in the smallest tensile yield zone and the smallest compressive and tensile residual stresses. A welding configuration taking into account these considerations will result in an orthotropic steel bridge deck with a longer fatigue lifetime. Barsoum, Z., Lundbäck, A., 2009. Simplified FE welding simulation of fillet welds – 3D effects on the formation residual stresses. Engineering Failure Analysis Vol. 16, pp. 2281-2289. Bonifaz, E.A., 2000. Finite element analysis of heat flow in single-pass arc welds. Welding research supplement, pp. 121s-225s. Goldak, J.A., Chakravarti, A.P., Bibby, M., 1984. A new finite element model for welding heat sources. Metallurgical Transactions 15B, pp. 299 305. Lindgren, L.-E., 2006. Numerical modelling of welding. Computer methods in applied mechanics and engineering Vol. 195, pp. 6710-6736. Shan, X., Davies, C.M., Wangsdan, T., O’Dowd, N.P., Nikbin, K.M., 2009. Thermo -mechanical modelling of a single-bead-on-plate weld using the finite element method. International Journal of Pressure Vessels and Piping Vol. 86, pp. 110-121. Wen, S.W., Hilton, P., Farrugia, D.C.J., 2001. Finite element modelling of a submerged arc welding process. Journal of Materials Processing Technology Vol. 119, pp. 203-209. References