Modernization of Steel Trusses Made of Square and Rectangular Hollow Sections

The purpose of this study is to investigate the stress-strain behavior of nodes in purlin trusses fabricated from square and rectangular steel tubes. In modern steel construction, ensuring optimal material utilization and structural reliability is essential. The research aims to identify the causes of uneven stress distribution in conventional truss joints and to explore innovative reinforcement methods. By addressing the low utilization coefficient inherent in standard connections, the study seeks to develop a reinforcement strategy that enhances load-bearing capacity without altering the overall geometry of the structure. In the presented work, an advanced numerical analysis was carried out using the finite element method in combination with the specialized IDEA StatiCa software. A detailed computational model of the truss nodes was developed to assess the internal force distribution and to pinpoint critical zones where stress concentrations occur. The investigation involved iterative simulations and parametric studies to evaluate the effectiveness of incorporating intermediate reinforcement elements, such as strengthening plates, into the node configurations. The simulation results revealed that conventional unreinforced connections exhibit significant local overstressing, which limits the effective use of steel. In contrast, the introduction of targeted reinforcement produced a more uniform stress distribution and resulted in an increase in the overall load-bearing capacity of the truss system by approximately 1.45 times. The comprehensive analysis confirms that advanced modeling techniques can reliably predict the benefits of design modifications for enhanced structural performance. The results of this study confirm that the integration of intermediate reinforcement in purlin truss nodes substantially improves structural efficiency and load capacity. The optimized design achieves a more even stress distribution and minimizes the risk of local failures without requiring any changes to the truss geometry. Advanced finite element analysis has proven to be a crucial tool in identifying critical stress zones and guiding effective reinforcement strategies. Consequently, the proposed methodology offers a viable solution for modernizing steel truss systems in both civil and industrial applications, ensuring enhanced safety and material efficiency.