Study Of P-Delta Effects Under Different Seismic Load Combinations For High-Rise Reinforced Concrete Buildings

Abstract

This research investigates the P-Delta effects-geometric nonlinearities caused by the interaction of axial forces and lateral displacements on high-rise reinforced concrete (RC) buildings under various seismic load combinations. These second-order effects, which are negligible under gravity loading but pronounced under seismic loading, can significantly amplify displacements and internal forces, thereby threatening the structural integrity and stability of tall buildings. The study aims to investigate and quantify the influence of P Delta effects by using different seismic load combinations of major design codes such as ASCE 7-22, NBC 105, and IS 1893. On the basis of detailed structural modelling and analysis using simulation programs such as ETABS, the study assesses internal forces, lateral displacements, and stability criteria due to second-order effects. Comparative study of international seismic codes enables the identification of the most critical load combinations for P-Delta instability. Outcomes are expected to assist in the development of more seismic-resistant structural design approaches for high-rise buildings in earthquake-prone areas. Last but not least, this research aims to bridge shortcomings of current design practice by providing evidence-based recommendations for the incorporation of P-Delta effects into structural analysis and design procedures for the improved safety and performance of tall RC buildings under seismic loads.