Laboratory investigation of stress-strain characteristics of fly ash based composite

Abstract

About 75% of India's energy supply is from 120 coal based thermal power plants and produce about 160 mt of fly ash in 2009. An estimate shows that, a 200 MW power plant generates about 80 tonnes of fly ash per hour. According to Gazette of India 2008, "fly ash" means and includes all categories or groups of coal or lignite ash generated at the thermal power plant such as electrostatic precipitator (ESP) ash, dry fly ash, bottom ash, pond ash and mound ash. Dumping of fly ash occupies huge land space (about 1,00,000 acres in 2005), and it is estimated that about one acre per MW of land is needed for its disposal. Fly ash produced as a result of burning of coal has detrimental effects on environment. There are ample scope for its environmental friendly utilization in different applications in underground mines such as a raw material for backfill, support unit, construction work in underground coal mines as well as for recultivation and restoration purposes of opencast mines due to its pozzolanic characteristics. In this work, an investigation is carried out to develop a fly ash based composite of considerable compressive strength. The composites thus developed can be used to make a load bearing units in an underground mines.