Effect of Staging and Shape in RCC and Precast Elevated Water Tanks

Elevated water tanks are vital components of urban and rural water supply networks, functioning as lifeline structures whose performance during seismic events directly impacts public safety and infrastructure resilience. The staging system, which supports the tank container, plays a crucial role in governing the dynamic behavior of the structure under lateral earthquake forces. However, conventional design approaches lack comprehensive comparative evaluation of different staging configurations, particularly in high seismic zones where stiffness, displacement, and time period significantly influence structural stability. This study investigates the seismic performance of elevated water tanks by comparing reinforced concrete (RCC) column staging and RCC shaft staging systems through detailed analytical modeling and dynamic response assessment. A three-dimensional structural model is developed and analyzed using response spectrum method in accordance with IS 1893 (Part 2) seismic provisions. Key response parameters including base shear, lateral displacement, natural time period, stiffness, and overall stability are evaluated for both staging arrangements. The results indicate that RCC shaft staging exhibits higher stiffness, lower displacement, and reduced time periods compared to column staging, demonstrating superior resistance to seismic forces. The findings highlight the significance of optimized staging selection to enhance seismic safety, serviceability, and structural reliability of elevated water tanks. This study contributes to improved design insights for earthquake-resilient water storage infrastructure in seismically active regions.