Seismic Performance Evaluation of Multi-story Buildings using Optimal Pozzolanic Material

Abstract

Earthquakes, characterized by sudden and transient movements of the Earth’s surface, have shaped the planet for millions of years, long before human habitation. Modern construction practices continue to face challenges in designing earthquake-resistant structures, prompting interest in pozzolanic additives such as Rice Husk Ash (RHA) and Silica Fume (SF). However, their optimal use in seismic design remains unclear. This study models a 20-story high-rise building in Extended Three-Dimensional Analysis of Building Systems software (ETABS), following Eurocode 8 standards, to evaluate the seismic performance of different concrete types, including conventional concrete (NC) and mixes incorporating RHA and SF. Material properties were sourced from literature, and beams, columns, and slabs were defined accordingly. Results show that NC provides superior dynamic stability, while RHA and SF concretes introduce higher flexibility and deformation, requiring targeted design adjustments. Specifically, NC exhibited modal periods between 0.626 s and 5.012 s, RHA concrete between 0.606 s and 4.86 s (indicating slightly increased stiffness), and SF concrete between 0.822 s and 6.598 s (indicating higher flexibility). RHA improved durability with minimal stiffness reduction, while SF enhanced vertical load transfer but increased lateral forces, leading to greater drift and displacement. Although all drift values remained within Eurocode 8 limits, base shear increased by 9.61% for RHA and 17.14% for SF, confirming improved lateral resistance. These findings highlight that incorporating pozzolanic materials can enhance certain structural properties but requires careful adjustment of seismic design parameters to ensure safe and resilient implementation in real-world high-rise construction. Member-level recommendations suggest using RHA concrete for columns and critical beams, NC/RHA for slabs, and SF selectively, while a hybrid system with RHAC in primary elements and SFC in non-critical members offers the best balance of stiffness, ductility, and seismic resilience.