# Overview of FEM-Based Resistance Models for Local Buckling of Welded Steel Box Section Columns
## 2 Literature Review
### Further Related Research Activities  
To avoid local buckling in thin-walled members, one viable alternative involves increasing the plate stiffness, adding stiffeners along the longitudinal axis, as presented in [13] or [14]. These options effectively prevent the inward buckle pattern, compelling the structure to shift to higher buckling modes while concurrently bolstering its load-bearing capacity. Several experimental tests have been conducted to assess the effectiveness of these techniques in improving the local buckling load resistance. In a study by [PERSON] and [PERSON] [14], four specimens served as reference values to investigate the ductility and large energy absorption capacity achieved through the use of confined concrete. Furthermore, [PERSON] and [PERSON] [2] tested 11 specimens to evaluate the applicability of the existing design guidelines. The creation of a computational-numerical model for analyzing the buckling failure mode of welded thin-walled members has been dealt with in previous works. However, they were primarily focused on interaction of buckling failure modes and making adjustments to equations and partial factors available in the existing building codes. The following is a list of relevant papers using FEA instead of physical tests to assess the local buckling failure mode. The findings of these papers were discussed in the validation and calibration phase of the computational model developed in this research. * The research conducted by [PERSON] et al. [15] studied the interaction between the flanges and the web of a hollow section columns, considering the independent buckling behavior in each plate. To achieve this, they performed a parametric study to derive a local buckling coefficient for the combined effects of axial compression and bending actions. The numerical tools employed in their investigation included GBTUL 2.0 and CUFSM 3.13. * [PERSON] et al. [16] explored the influence of imperfections, such as residual stresses resulting from the welding process and initial global bow imperfection. Their work was supported by a combination of experimental and numerical investigations, leading to a proposal for modifying the non-dimensional slenderness equation used in global buckling verification. Additionally, they proposed an alternative to the current European buckling curve for welded box section columns. * In the study by [PERSON] et al. [17], the effective width of the plate in thin-walled sections was investigated, and an evaluation of [PERSON]'s formula was conducted. This research was carried out with the aid of FEA. * [PERSON] et al. [18] presented their research findings on the influence of the fabrication process on buckling phenomena in thin-walled steel sections. Their aim was to propose a buckling curve specific to welded thin-walled members. * [PERSON] and [PERSON] [19] studied and modified the Ayrton-Perry-type buckling formula to implement the effects of residual stresses and geometrical imperfections in the design procedure. This study was based on theoretical reviews and numerical analyses. Welded steel box section columns, constructed from four flat plates, are typically produced using one of the plate arrangements shown in Figure 1. The weld position influences the pattern and magnitude of residual stresses, stemming from the heat generated during the welding process. As a result, differences in residual stress distribution and intensity are observed among plates A, C, B, and D for types 2 and 3. In contrast, type 1 exhibits a uniform residual stress distribution and intensity across all plates. In this research program, all studies on welded square box sections were compiled in order to present a general proposal. The data collected from experimental research programs are summarized in Table 1. The total number of tests was determined exclusively from experiments conducted on welded square sections without any additional stiffeners and subjected to pure compressive load.