High-accurate FE simulation on compressive behavior of steel cruciform column with welding imperfection

Abstract

Due to its various advantages, welding is commonly used in the construction for steel connection. However, the local temperature difference in the welding causes welding deformation and residual stress. The welding deformation and residual stress can significantly impact the load-bearing performance of members. Therefore, it is important to evaluate those behaviors with high precision. In the previous studies, thermal elastic-plastic analysis was used to evaluate welding deformation and residual stress in simulated welded specimens and the compressive simulation was applied to obtain, for example, the load-bearing performance. Nevertheless, there are limitations in assessing structures made up of thin plates. This is because the simulation of welding is typically modeled using solid elements, while the simulation of loading analysis uses shell elements. As a result, these analysis steps are not directly related, leading to deficiencies in the evaluation process. In this study, the solid element model and shell element model were modeled to simulate the welding deformation and residual stress. The corresponding load-bearing capacity results obtained from the continuous loading analysis were compared with the results from experiment to verify the consistency. According to the results, shell models that perform welding analysis simulation followed by continuous compressive analysis are better able to replicate experimental results in terms of out-of-plane deformation and maximum load-carrying capacity under compressive analysis. This is in contrast to solid models, which fall short in reproducing the same results. Moreover, the shell model is also more efficient than the solid model in terms of time saved during analysis and calculation.