Comparative analysis of performance under seismicity, wind variability, and coastal environments across 16 prominent Indian urban centers: Hybrid tanks versus standard RCC water tanks

Abstract

This study has compared Hybrid Tanks and Standard RCC water tanks in 16 prominent cities across India, considering diverse seismic zones, wind speeds, and the influence of coastal and non-coastal variations. The chosen cities have represented a range of seismic zones: Bhopal, Hyderabad, Jaipur, Puducherry (Zone II); Ahmedabad, Vadodara, Lucknow, Chennai (Zone III); Shimla, Alibag, Delhi, Dwaraka (Zone IV); and Mandi, Kohima, Imphal, Guwahati (Zone V). Encompassing all seismic zones and considering wind velocities of 39 m/s, 44 m/s, 47 m/s & 50 m/s, the study has designed 600 kL Intze water tanks utilizing C++ software programs developed for both tank types. The findings have revealed that seismic base shear has significantly increased as seismic zones have progressed, with rises of approximately 60%, 140%, and 260% in Zones III, IV, and V, respectively, compared to Zone II. Coastal cities have experienced higher wind shear forces, leading to increased costs. Wind forces have often surpassed seismic forces in coastal regions. Tank costs have risen with changing wind speeds and seismic activity zones, particularly in coastal areas, for both Hybrid and Standard RCC tanks. These findings have emphasized the crucial role of considering seismic zones, coastal effects, and wind dynamics in water tank infrastructure design and construction.

Hybrid tanks outperform Standard RCC ones with 22-23% cost savings, 28% less concrete (38.6% in body, 12-15% in staging), and 17.5% less steel (13.3% in body, 19.9% in staging). They have shown reduced base shear (up to 5% full, 15% empty), 5% less bending moment, 11% less deflection (full), 40.1% less deflection (empty), and a crack width has been reduced by 63-87 % making them a promising alternative nationwide.