## 3 Materials and Methods
Although the granted ductility of construction steel is 15%, the real usable value of limit plastic strain is 5% for an ordinary design [22]. The stress in steel cannot exceed the yield strength when using the ideal elastic-plastic stress-strain diagram. The CBFEM method aims to model the real state precisely. Meshes of plates from different components are not merged, and no intersections are generated between them. Instead, a mesh of finite elements is generated on each individual plate independently on mesh of other plates. Between the meshes, special massless force interpolation constraints are added. They ensure the connection between the edge of one plate and the surface or edge of the other plate. End forces on members are applied as loads on segment ends, with internal forces from theoretical nodes transferred to segment ends, maintaining force values while adjusting moments due to force actions on corresponding arms, without connecting inner ends of segments [16]. The model incorporates shear stress transmission by crushing and tensile-shear interaction. This unique calculation model provides excellent results, both from the point of view of precision and a speed analysis. Figure 2 illustrates the joint model as displayed by IDEA StatCa. Circular holes are arranged both in the IPE240 profile and in the plates. As stipulated by Eurocode 3 Part 1-8 [17] for M12 and M14 bolts, the standard diameter of the holes equals the diameter of the screw shank plus 1 mm (Figure 3). Spacing between bolts and between bolts and the plate border is regulated by Eurocode 3 Part 1-8. Figure 2: Joint model in IDEA StatCa using finite elements with the range of colors representing the state of internal tensions. The case studies assume a small bending moment value in relation to the shear stress. This fact determines the placement of joint covers only in the web zone of the structural section. A total of 80 case studies were analyzed with the same static loading hypothesis, including the weighting coefficients of actions, resulting in a bending moment stress of 10 kN-m and a shear stress of 75 kN. These values constitute the boundary conditions, with no additional constraints considered. As a result, the model is in equilibrium after computation if the internal forces are added at the ends of related members. Table 1 contains model and mesh CBFEM parameters as well as calculation parameters as introduced in IDEA StatCa settings. A multiple of the height of the section is used to determine the default length of a standard element. The ratio of the plate edge length to the number of edge elements determines the number of elements in the largest flange or web. Each calculation was conducted with 25 iterations with up to three divergence steps for its evaluation. The finite element mesh is composed of linear elements. To select the size of the finite elements, a pilot sensitivity analysis was conducted. Element sizes of 2 to 8 mm, 5 to 20 mm, and 10 to 40 mm were set to analyze the effect of the mesh size on the target parameters of this study. It was concluded that reducing the mesh size beyond the latter values did not provide significant additional precision while the computational time was greatly increased. As a result, the maximum element size was set at 40 mm and the minimum element size was set at 10 mm since it provided a sufficient fineness to obtain precise enough results without delaying the computational calculation, while the mesh layout provided sufficient adaptation to the shape of the connection components. The results of joint designs have been further checked and validated using the spreadsheets for lateral bolted joints prepared by [PERSON] et al. [1] These are based on the abovementioned EuroCode 3 specifications.