The comparative study between HSS and WF section as braced toward seismic performance of concentrically braced frame in multi-storey steel building

The rapid growth of global industrial sector has increased the demand for earthquake-resistant industrial buildings, particularly in Indonesia. Steel structures with Concentrically Braced Frames (CBF) are popular option due to its efficiency in resisting lateral seismic forces through bracing elements. These braces can be fabricated from various steel profiles, such as Hollow Structural Section (HSS) and Wide Flange (WF) sections. This study compares the seismic performance of multi-storey buildings with CBF using HSS and WF profiles as bracing elements. Nonlinear static pushover analysis was conducted using ETABS v18 on five-story industrial building models, employing HSS and WF sections that have equivalent cross-sectional areas. The resulting capacity curves were used to develop fragility curves based on HAZUS methodology to estimate the probability of exceeding different damage states named as slight, moderate, extensive, and complete damage. The results illustrated that CBF structures with HSS bracing exhibit higher base shear capacity, stiffness, and overall strength, while WF bracing demonstrates greater ultimate displacement and ductility. Therefore, HSS bracing is more suitable for industrial buildings that demanding serviceability is crucial, whereas WF bracing is advantageous in conditions where energy dissipation and deformation capacity are prioritized.