Strength and Hydraulic Conductivity of Lime Stabilized Fly Ash

Abstract

Massive urbanization in the recent times has led a high increase in the power demands and eventually an increase in the production of fly ash generated as a waste material from thermal power plants which gives rise to lots of environmental and disposal problem. To decrease the environmental pollution and hazardous effects, it is imperative to utilize fly ash as a construction material in civil engineering. But fly ash as such does not have enough strength to be used as a construction material. So, it is advisable to improve the engineering properties of the fly ash by stabilizing it by adding other materials or additives. In present investigation fly ash is stabilized with lime i.e. calcium hydroxide (in different proportions (0, 2, 4, 8, 12%) by means of total weight (fly ash + lime) and the compaction characteristics, strength and hydraulic conductivity of the resultant mixture were determined by modified proctor test, Unconfined Compressive Strength Test (UCS) and falling head permeability test respectively. The UCS samples and permeability samples were prepared to correspond to particular maximum dry density (MDD) and optimum moisture content (OMC) and cured for 0, 3, 7, and 28 days under a constant temperature of 270C and the unconfined compressive strength (UCS) and coefficient of permeability (k) were determined. The results showed though there is not much alteration in maximum dry density and optimum moisture content with increasing lime content but it has been also observed that the presence of Ca(OH)2 has pronounced effect in enhancing the UCS manifolds of the stabilized fly ash specimens whereas the coefficient permeability decreased with increasing curing period.