Laboratory Investigation on Performance of Expansive Soil Stabilized by Fly Ash and Sodium Hydroxide

Expansive soils pose serious problems in geotechnical engineering applications because of their swelling-shrinking tendency during alternate wetting and drying cycles. The presence of predominant clay minerals in these soils make it susceptible to volume change with variations in moisture. The wetting and drying makes the soil leading to the failure of foundations of structures constructed over it. The potential usage of fly ash and NaOH (sodium hydroxide) through the engineering properties of soil was studied by carrying out the geotechnical tests such as Sieve analysis, consistency limits, standard proctor compaction, and unconfined compressive strength (UCS). From the experimental findings, the UCS of stabilized soil is found maximum for 15% of fly ash alone and is considered as optimum. Further, the soil is amended with optimum % of fly ash and NaOH solution varied at 1 N, 2 N, 3 N, and 4 N is used as pore fluid. The present study indicates that both fly ash and sodium hydroxide can be effectively utilized to stabilize the expansive soils.