Rational design of braced steel structures using the example of a lattice column

<ns3:p>The aim of the study was to develop guidelines for the rational design of braced steel structures using a 2D tower model as an example. The analyzed structure was 20 meters high and 4 meters wide, consisting of columns, horizontal beams, and X-type bracings. Seven bracing configurations were considered, with bracings placed across two to seven levels. All structural elements were made of S235 steel. Bracings were modeled as solid round bars, beams as SHS profiles, and columns as catalog sections: HEA, HEB, SHS, and CHS. A total of 367 column cross-sections were analyzed across seven bracing layouts. Design guidelines for bracings were presented and discussed, with a focus on eliminating lateral-torsional buckling, based on two key criteria: stiffness and load-bearing capacity. Structural calculations were carried out using Robot Structural Analysis software, applying a linear buckling analysis (LBA) with reduced stiffness. In total, 2,202 towers with optimally selected bracings and beams were designed. The results were compiled to show structural efficiency (tower capacity to weight ratio) depending on the slenderness of the columns. It was found that the most effective designs used low-slenderness columns, and the mass of bracings and beams should generally not exceed 25% of the total tower weight.</ns3:p>