Influence of the end vertical member length on the design of steel roof trusses

The introduction of steel into Brazilian civil construction in the late 19th and early 20th centuries marked a turning point, with domestic production gaining prominence following the establishment of the National Steel Company (Companhia Siderúrgica Nacional) in 1946. Steel’s high strength and ductility have made it indispensable for large-scale projects, offering execution efficiency and recyclability. However, its high production costs and energy consumption raise environmental concerns, as the steel industry contributes significantly to global CO2 emissions. Within this context, this study investigates the influence of the end vertical member length on steel consumption and the sizing of steel sections in roof trusses. Using the Finite Element Method (FEM) through a computational tool developed in Python, 21 simulations were performed, varying the vertical member length from 0 to 100 cm in a Howe truss with a 24-meter span and a 10% slope in the top chord. The results indicated a 52% reduction in steel mass between the extreme values, highlighting the importance of geometric adjustments to optimize material consumption. Increasing the vertical member length redistributed internal forces, enabling the use of lighter sections. These findings underscore the relevance of optimization in structural design to promote sustainable solutions, reducing resource consumption and the environmental impact of steel constructions.