Comparative analysis of high-rise building behaviour using base isolation and virtual outriggers

There is a huge demand for housing to meet shelter needs as a result of the growing population and land shortage. For engineers, meeting the housing demand in the face of this expanding population has become a major challenge in recent years. The construction of tall buildings, or high-rise buildings (HRBs), is thought to be an efficient way to address this problem. Wind and seismic forces are important considerations in high-rise building design, which increases the susceptibility of structures to vibrations. Numerous lateral load-resisting systems, such as shear walls, belt trusses, outriggers, base isolation, staggered trusses, and tube-in-tube systems, are available to control these vibrations or displacements. One common method used to shield high-rise buildings from seismic forces is base isolation. To separate the superstructure from the substructure, a variety of base isolators or bearings are used nowadays, including ball and roller bearings, curved slider bearings, high-damping bearings, elastomeric bearings, lead rubber bearings (LRB), and pendulum bearings. Nonetheless, outrigger systems are thought to be among the best ways to improve high-rise buildings' overall stability and lateral stiffness. ETABS 2020 software is used in this study to model and analyze a 30-story grid-plan high-rise building in seismic zone V with and without the virtual outrigger and base isolation system. LRB is used as the base isolation system, and a steel belt truss is used as the virtual outrigger. A response spectrum analysis is conducted to evaluate various structural response parameters, including storey displacement, storey drift, overturning moment, base shear, and modal time period under earthquake loads.