Performance of Fly Ash - Lime Stabilized Lateritic Soil Blocks Subjected to Alternate Cycles of Wetting and Drying

The study investigated the durability performance of lime and fly ash stabilized lateritic soil blocks subjected to conditions of alternate wetting and drying. A locally available lateritic soil was collected and characterized in the laboratory for its geotechnical properties. The soil was then stabilized using lime and fly ash of various combinations. The blocks were tested for their compressive strength, water absorption and efflorescence. Durability was evaluated by subjecting the blocks to three cycles of wetting and drying and testing its compressive strength. The investigation revealed that fly ash-lime stabilization was capable of producing stabilized blocks meeting the standard requirements of Indian codes in terms of compressive strength, water absorption and efflorescence. The results revealed that a combination of 10 % fly ash with 10 % lime was enough to stabilize the soil to achieve the strength of a class 20 block whereas a combination of 10 % fly ash and 14 % lime was required to achieve the strength of a class 30 block. Wetting and drying cycles resulted in a marginal increase in strength after the first cycle but reduction thereafter. The optimal combination of 10 % fly ash and 14 % lime resulted in less than 25 % loss in strength after three cycles of wetting and drying.