Economic Design of Water Tank of Different Shapes With Reference To IS: 3370 2009

Abstract

The conventional method of designing water tanks which is working stress method outlined in the previous version of IS: 3370 1965 is irrational and leads to relatively thicker sections with a substantial amount of reinforcement. Limit state method which is widely used has been recently adopted in the new version of IS 3370-2009 concrete structures for storage of liquids - code of practice. For quick cost prediction of tanks, this study therefore examines the cost effectiveness in terms of amount of materials and formwork used for Circular, Square and Rectangular overhead water tanks each of three capacities of 100kl, 150kl, 200kl and draw reasonable inferences on tank's shape design effectiveness . Each water tank was designed by Limit State method and then the crack width was checked by limit state of serviceability IS 3370 (2009). The results have been presented in the form of graphs and tables and it has been observed that Circular-shaped tank consumed lesser of each material as compared to Square and Rectangular ones. The amount of formwork required for circular tank is also less than that for square and rectangular tanks thereby giving Circular-shaped tanks a more favorable selection over the rectangular and square shaped tanks.