The Use of Fly Ash and Lime Sludge as Partial Replacement of Cement in Mortar

The increased demand of drinking water and power has led huge generation of water treatment plant residue i.e. sludge and the thermal power plant by-product such as fly ash. Large quantities of sludge and fly ash are produced in India and disposed off by landfilling or dumping in and around sites. In this study fly ash and water softening sludge (lime sludge) has been utilized in mortar. Two types of mortar (type I and II) with four binder combinations have been tried. Binder I consists of 70% fly ash (FA) and 30% lime sludge (LS) , 0 % gypsum (G), binder II is 70% FA, 30% LS and 1% G, binder III is 50% FA, 30% LS and 20% cement and the binder IV is 40% FA, 40% LS with 20% cement. The effect of various combinations on strength has been discussed here. This paper outlines the composition of the composite material, method of preparation of mortar specimen, testing procedure and salient results thereof