Influence Of Fly Ash On Compaction Characteristics Of Expansive Soils Using 2~2 Factorial Experimentation

摘要

Expansive soils undergo volume changes due to gain in moisture or loss thereof.rnStructures founded on such soils experience severe damages. Fly ash is a hazardous mineral residue resulting from the combustion of coal and its disposal causes environmental pollution. The bulk utilization of fly ash is possible by stabilizing the soils using fly ash in the construction of structures such as embankments, pavements, and earth retaining structures where soil is used as a construction material. The objective of the present investigation is to evaluate optimum fly ash content for stabilization of the expansive soils from the view point of compaction characteristics. An attempt has been made to know the effect of two factors namely fraction coarser than 425μ and liquid limit as well as their interaction effect on optimum fly ash content, change in maximum dry unit weight and change in optimum moisture content due to addition of optimum fly ash content. An experimental strategy called 2~2 Factorial Experimental Design is adopted in conducting experiments which enables relative quantification of effect of factors under consideration as well as their interaction on response of interest. Liquid limit is found to have a dominating influence on Optimum fly ash content, changes in compaction characteristics due to addition of optimum fly ash. Multi linear regression models were evolved for prediction optimum fly ash content, percentage increase in maximum dry unit weight and percentage decrease in optimum moisture content in terms of influencing main and interaction factors.