A Review on Seismic Issues and Remedies in High-Rise Structures

The increase in population in urban areas have popularised high rise structures, as a means of accommodating more people in a limited area. The major concerns in the designing and construction of high-rise structures are the safety aspects against wind and earthquake forces, as the collapse of the structure can lead to a disaster. The seismic zoning map of India shows that a large area of India is prone to earthquakes. The growing use of high strength and lightweight materials in high-rise structures makes them more flexible and lightly damped, thereby making these structures more sensitive to dynamic excitations. Presence of irregularities, setbacks, open ground story, weak and soft storeys, also increases the seismic vulnerability of high-rise structures. Vertical ground shaking can be of significant concern in terms of amplification of acceleration along the height of the building, and also, achieving vertical isolation had been challenging as the gravitational load must be sustained by the isolation system. Quasi-Zero stiffness system was found to be effective in vertical isolation of structures. Installing damping devices at optimal locations, base isolation systems, and suitable seismic retrofitting strategies can enhance the seismic performance of structures. This paper reviews the various factors that lead to seismic issues in high-rise structures such as size, shape, configuration, structural aspects, and material properties. The appropriate remedies to address the seismic issues are also reviewed.