Strength Characteristics of Kuttanad Soil Stabilized with a Biopolymer Guar Gum

Abstract

AbstractKuttanad soils are low strength soft clay or silt deposits found in the Kuttanad areas of the Alappuzha district, Kerala. Due to its low load-bearing and high shrinkage characteristics, the structures and pavements constructed over were unstable. Treatment with appropriate chemical additives is one of the accustomed and economic techniques in soil stabilization practice for improving the characteristics of weak soil. Traditional stabilizing agents like cement, lime, etc. are becoming less environmentally friendly and costly. This paper focuses on the influence of a non-traditional soil stabilizer guar gum, which is a biopolymer on the strength characteristics of low strength and highly compressible Kuttanad clay soil. Biopolymers are environment-friendly polymers produced by living organisms like plants. The lack of sufficient research to understand its impact on soil behavior has minimized the use of biopolymers to become widely accepted for soil modification purposes. Samples prepared with varying dosages of biopolymer (0.5–2.5%) were cured for a period of 7–28 days without moisture loss to study the influence of aging effect on strength parameters. Strength characteristics such as compaction, unconfined compressive strength, and California bearing ratio strength (CBR), etc. of stabilized samples were determined. Results showed that there is considerable improvement in the strength characteristics of soil with the inclusion of guar gum and with the curing period. Observing the tremendous improvement in the CBR strength value of soil within 28 days of curing, soil stabilization using guar gum may be recommended for effective and faster stabilization of weak subgrade soils for construction activities.KeywordsUnconfined compressive strengthBiopolymerClay soil stabilizationKuttanad clay