Influence of Vertical Irregularities of Various Steel Framed Structures During Seismic Response
Keywords:
Seismic loads, vertical irregularities, steel buildings, and steel-braced structures are some of the terms used to describe these factors.Abstract
Severe torsion forces, in addition to lateral forces, are exerted on buildings that are vertically irregular, asymmetric in plan and elevation, or both, by the action of earthquakes. Plan and elevation views of buildings with vertical irregularities are highly asymmetrical because the centers of mass and stiffness of individual floors are not all on the same vertical axis. The steel construction industry is vital to the building sector. Earthquakes in India's past have demonstrated the importance of designing engineered structures to withstand seismic forces. Adding steel bracings to the structural system of a steel moment-resisting frame improves the frame's response. A significant factor influencing structural responses to seismic loads is irregularity. METHODOLOGY AND EXPLANATION The purpose of this research is to analyze the seismic responses of steel buildings for two types of vertical irregular buildings: vertical irregularity associated with steps in the building plan area (Brace system with full height and frames that have more bays at the base of the building than at the top) and (ii) vertical irregularity associated with Brace system that stops around mid-height of the building. Using linear static analysis, we compared the behavior of low-rise and high-rise steel buildings with vertical irregularity and identical bay lengths. To further investigate the nonlinear response of all structures to the Chamoli earthquake, a nonlinear time history analysis is performed.
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