PSI - Issue 70

Milena Carolina Derlam et al. / Procedia Structural Integrity 70 (2025) 3–10

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1. Introduction The Light Steel Framing (LSF) system has emerged as an innovative construction solution in the Brazilian market, offering advantages such as lightness, fast execution, material rationalization, and cost reduction. However, the lack of consolidated normative guidelines for structural design, particularly regarding the use of Oriented Strand Board (OSB) panels as bracing elements, limits the widespread adoption of this system nationally (Chen, 2023). The slenderness of Cold-Formed Steel (CFS) profiles used in LSF makes the structures particularly susceptible to instabilities, such as buckling and horizontal displacements, requiring effective bracing systems, especially in shear walls (Niari et al., 2015). The stiffness of these walls is strongly influenced by factors such as the type of sheathing and, most notably, the screw spacing used to fasten the OSB panels - an element that directly affects the overall performance of the system (Yilmaz et al., 2023). Several studies have examined the structural performance of OSB-sheathed shear walls under both static and cyclic loading conditions. For instance, Yilmaz et al. (2023) conducted numerical analyses on the performance of OSB sheathed walls subjected to lateral and vertical loads, while Blais and Rogers (2006) experimentally evaluated the seismic performance of steel-sheathed panels under static and cyclic loading. Both studies have produced important data that significantly contribute to the technical advancement and design optimization of these structural systems, while also providing validation of the results against those reported by Blais and Rogers (2006) and Yilmaz et al. (2023). In this context, the numerical investigation of screw spacing and distribution has proven essential for optimizing the stiffness, energy dissipation capacity, and deformation behavior of shear walls subjected to lateral displacements. Xie et al. (2020; 2024) highlighted that the use of reinforced connections, in conjunction with optimized screw spacing, can lead to significant improvements in shear resistance - an essential factor in the structural performance of LSF systems. Despite these advancements, a significant gap persists in the Brazilian technical literature regarding the direct effects of screw spacing on OSB-sheathed shear walls - especially in numerical studies tailored to local materials and construction practices. The lack of a comprehensive normative framework poses challenges to the safe and efficient design of these systems, ultimately limiting their application in larger-scale buildings. Given these challenges, the use of advanced numerical modeling tools has become essential for understanding the structural behavior of shear walls and optimizing their design parameters. This study aims to numerically investigate, using the Finite Element Method (FEM), the influence of screw spacing in double-sided OSB-sheathed LSF shear walls. The simulations were performed using Abaqus CAE (2024) to evaluate how different screw spacing configurations affect structural stiffness, energy dissipation capacity, and the overall performance of the walls under lateral loading. The results aim to contribute valuable technical insights to inform future design codes and promote greater efficiency and structural reliability in LSF within the Brazilian construction context (Simulia, 2024). 2. Modelling assumptions As demonstrated, advanced simulations using the FEM are capable of accurately predicting the in-plane global behavior and failure modes of shear wall panels composed of CFS profiles sheathed with OSB boards. For comparative results, three shear wall panels were analyzed, named “Model 75”, “Model 100”, and “Model 150”, were developed using the Abaqus CAE (2024), consisting of CFS profiles sheathed on both sides with OSB, as presented in Fig. 1. For each analysis, the OSB was fastened to the structural elements considering self-drilling screws, spaced at 75, 100, and 150 mm along the panel's outer perimeter in the three distinct tests, respectively. For connecting the sheathing to the inner stud, as well as the connections between the studs, a fixed screw spacing of 305 mm was adopted. The connections between studs and tracks were positioned centrally relative to the elements, always maintaining 10 mm from the outer edge.