Assessment of computational weld mechanics concepts for estimation of residual stresses in welded box structures

Paper in proceeding, 2019

In this study finite element simulation approaches (lumping and prescribed temperature) are implemented to study residual stress distribution in a welded box type structure. This component is a vital part in several load carrying structural applications and the residual stresses are important to quantify from a structural integrity point of view. The thermal history from simulations has been verified with experimental measurements. The residual stresses at the weld toe side were measured, using X-ray diffraction technique. It is shown that a similar trend of residual stress state was captured by the simulation, compared to experimental measurements. The estimated residual stresses from the cases of welds with full penetration and partial penetration are slightly different along the crack path. Compressive residual stress was near the area of both weld toe and root while tensile residual stress was in the center of the weld with the magnitude up to 820 MPa. Moreover, a sub model of the welded box type structure is studied using the following computational weld mechanics concepts: Thermo -elastic -plastic, lumping and prescribed temperature, in order to assess the computational time and the magnitude of estimated residual stresses.