Cost Analysis of RC Buildings in Different Seismic Zones

Abstract: Reinforced cement concrete buildings are widely used in India because they offer a practical balance of strength, durability, and economy. However, seismic zone classification has a major influence on structural design, reinforcement demand, and overall construction cost. This paper presents a comparative study of a G+6 RCC framed building designed for Seismic Zones II, III, IV, and V as per IS 1893:2016 and IS 13920:2016. The building was analyzed using standard seismic design concepts to evaluate changes in base shear, storey displacement, drift, reinforcement requirement, concrete consumption, and total structural cost. The findings show a clear increase in seismic demand as the zone severity increases. Base shear, member sizes, and reinforcement quantities all rise progressively from Zone II to Zone V, which leads to a noticeable increase in construction cost. The study confirms that seismic design is not only a safety requirement but also a cost-driving factor in multi-storey RCC construction. The results are useful for engineers who need to achieve a practical balance between structural performance and economy in earthquake-prone regions.

Keywords: RCC buildings, seismic zones, cost analysis, base shear, storey drift, reinforcement demand, seismic design, ETABS, IS 1893, construction cost.