###### Abstract
They introduced an analytical model to calculate the mechanical properties of steel-plate-reinforced segmental linings based on joint deformation and stress characteristics. The model was validated using FEM simulations. [PERSON] et al. (2024) [11] explored the use of boundary stiffeners and varying infill plate widths to improve the behaviour of the steel plate shear walls resisting lateral loads through analytical equations. The results showed that stiffeners increase strength, energy dissipation, and stiffness while reducing infill plate width without stiffeners weakening the system. [PERSON] et al. (2023) [12] examined the effect of patch configuration and position on stress concentration around stop-holes using a FEM analysis. It proposes a fatigue design equation incorporating patch configuration and position to help design effective repairs and evaluate remaining fatigue life in cracked steel structures. [PERSON] et al. (2024) [13] studied marine structures that often face combined in-plane and out-of-plane loads, but the impact of lateral loads on stiffened plates' ultimate strengths and collapse modes requires further study. The authors developed a testing device for combined load experiments and conducted three different load case tests using FEM. In [13], a FEM numerical parametric analysis was performed to explore the impacts of various parameters on the design of scaled-down stiffened plates under compression loads. In [14], a FEM model was also developed, validated with experimental data, and applied to evaluate the ultimate strength of stiffened plates under cyclic loads. Tests were conducted to observe hysteresis behaviours and to validate the assessment method. The central problem addressed in this research is the computational modelling of stress concentration at the tips of internal stiffeners, which adopt a triangular termination and are welded to the plates forming the walls of the crane legs. This research particularly emphasises the sea-side legs (without excluding those on the land-side), due to a fraction of the crane's centre of gravity, it is typically displaced towards the sea-side (especially at the working position at boom level, i.e., at 0\({}^{\circ}\)), which has significant implications for structural durability, operational performance, and corrective maintenance costs. Therefore, this problematic scenario justifies research and modelling of port STS cranes. The main objectives of this study include analysing and modelling stress distribution at the triangular tip terminations of internal stiffeners using two different methods: Finite Element Method (FEM) and Multiple Linear Regression (MLR) models. Additionally, the research aims to validate the statistical significance of results obtained through MLR models compared to FEM simulations, employing statistical multiple comparison methods. To achieve these objectives, a comprehensive methodology is employed, starting with the generation of a database using FEM simulations. This database incorporates key mechanical parameters and geometric features influencing stress concentration (P6), such as stiffener tip height (P1), stiffener to diaphragm separation (P2), leg web plate thickness (P3), stiffener thickness (P4), and applied load (P5) (see Figure 2). Subsequently, multiple linear regression models are used to estimate stress concentration, providing an alternative approach to traditional FEM simulations. The significance of this research extends beyond  
Figure 1: (**a**) Overview of an STS crane and its heightening, (**b**) Internal stiffeners of the legs, (**c**) Complete panel of the inner face of the leg, the study area has three stiffeners where symmetry conditions are leveraged to isolate the central one. the structural adaptation to mega container ships; it underscores the need to improve crane designs to mitigate costs associated with crack initiation and propagation, which necessitate frequent repairs, especially given the similar configurations of port cranes.