In the heart of India’s bustling urban landscapes, a silent sentinel stands guard over our daily lives: the overhead water tank. These reinforced cement concrete (RCC) structures, vital for municipal water supply, face an often-overlooked challenge—seismic forces. A recent study, led by Reddy Dasari Rajesh from the Department of Civil Engineering at Vignana Bharathi Institute of Technology, delves into the influence of tank geometry on seismic performance and cost, offering insights that could reshape water infrastructure development in India.
The study, published in the ‘E3S Web of Conferences’ (which translates to ‘Environmental Science and Sustainable Development Web of Conferences’), compares three common tank shapes—circular, rectangular, and Intze—each designed to hold 500 kiloliters. Using Staad.Pro software, Rajesh and his team modeled and analyzed these tanks, assessing their seismic performance based on the Response Spectrum Method outlined in IS 1893 (Part 2): 2014. Their focus was on key parameters like base shear, top displacement, material quantities, and construction costs across Indian Seismic Zones II, III, IV, and V.
The findings reveal a clear pattern: circular tanks shine in Zone II, where seismic loads are lower and symmetrically dispersed. “Circular tanks exhibit excellent performance in Zone II due to their uniform distribution of forces,” Rajesh explains. However, as the seismic activity intensifies in Zones IV and V, Intze tanks take the lead. These tanks show reduced displacement and cost, along with optimal limits of horizontal force, making them the top choice for high-risk areas.
Rectangular tanks, while common due to site constraints in urban areas, tend to perform poorly in seismic events and require more materials. “Rectangular tanks are often chosen for their ease of construction and site adaptability, but they come with a trade-off in seismic performance,” Rajesh notes.
The study’s conclusions suggest a geometrically based design approach: Intze tanks for Zones IV and V, and circular tanks for Zones II and III. This strategy not only enhances seismic safety but also offers economic benefits, a crucial factor for municipalities striving to balance infrastructure development with budget constraints.
The implications for the energy sector are significant. As urbanization continues to surge, the demand for reliable water infrastructure will grow. This research provides a roadmap for constructing earthquake-resistant water tanks, ensuring uninterrupted water supply even in the face of natural disasters. For energy companies involved in water infrastructure projects, this study offers valuable insights into cost-effective and resilient design options.
Rajesh’s work underscores the importance of tailored engineering solutions. “Each seismic zone presents unique challenges, and our findings highlight the need for customized designs that optimize both performance and cost,” he says. By adopting these recommendations, municipalities can build more robust and efficient water infrastructure, ultimately contributing to the overall resilience of urban environments.
As India continues to develop, the lessons from this study will be invaluable. The future of water infrastructure lies in smart, seismic-resistant designs that prioritize safety, efficiency, and economic viability. Rajesh’s research is a step in that direction, paving the way for a more secure and sustainable urban future.