Potential use of treated sewage in concrete to meet water crises in megacities

Abstract

Water scarcity is one of the most important issues in countries that are water stressed. In India the dependency on groundwater increased between 2004 and 2013 and this has led to a decline in the water table in every state due to growing requirements. Acute water shortage and high water demands are particularly common in the agriculture, industry and construction sectors. The construction industry is accountable for an enormous consumption of water as the Indian guidelines recommend the use of potable water (PW) for concrete. The current study investigates the use of treated sewage (TS) as mixing and curing water in concrete. Tests, including setting time, workability, compressive strength, rapid chloride permeability and water permeability, have been carried out on fresh and hardened concrete for each concrete mix. PW was replaced by weight in ratios of 50, 80 and 100% with TS in the mixing and curing of specimens. The water/cement ratio was taken as 0.45 for PW and TS concrete. Compressive strength and durability were tested after 7, 28, 56 and 90 days of curing. It can be concluded that TS has the potential to replace PW in mixing and curing and should be included in relevant guidelines.