A review on soil stabilization using rice husk ash and lime sludge

Abstract

Building pavements and other civil engineering projects on available land containing some percentage of clay minerals is highly dangerous, due to its low strength properties. It is not always possible to avoid using that piece of land due to financial constraints. This necessitates soil treatment in order to improve soil engineering properties. In practice, admixtures like fly ash, lime, and cement are widely used to stabilize and strengthen soils. This study reviewed two waste materials: Rice Husk Ash (RHA) and lime sludge for stabilization because they are locally available nearby, the quantity of trash that must be disposed of and therefore reducing pollution. These two react to generate complexes that fill in the gaps in the structure of the soil, reducing shrink or swell characteristics and plasticity, and therefore enhancing the strength of the soil. RHA and lime sludge are waste products that can be found in large quantities, making construction more cost-effective. The present study aims at review of literatures pertaining to the stabilization of clay using RHA and lime sludge, separately and combined as well. It was observed that increasing the amount of RHA and lime sludge in the soil improves its strength. Additionally, to determine the best ratio of the two additives in order to maximize soil strength. The study on compaction characteristics, Liquid Limit (LL), Unconfined Compression Strength (UCS) and California Bearing Ratio (CBR) was focused from the literatures. Experiment results in the literatures with RHA and lime sludge from different studies are compared to determine the optimum quantity of RHA and lime sludge required to stabilize a weak soil, as well as inferences regarding the effect on soil attributes. By comparing the results, the suitable recommendations are provided. 10% RHA and 15% Lime sludge was found to be an optimum mix for the effective stabilization of clay.