TJES: Theyab AF, Muhauwiss F , Alabdraba WM, .Effects of Xanthan Gum Biopolymers on Gypseous Soils Characteristics. Tikrit Journal of Engineering Sciences 2021; 28(1): 22- 28.
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Tikrit Journal of Engineering Sciences (2021) 28(1) 22- 28.
Effects of Xanthan Gum Biopolymers on Gypseous Soils Characteristics
Gypseous soils are problematic soils that cause large deformations in the constructions that are built on it. Therefore, many binders have been used to reduce this impact. Traditional soil binders like lime or cement have environmental problems in terms of sustainability. Thus, sustainable substances have attracted appreciable interest in recently soil enhancement. Biomaterials are being developed to enhance geotechnical engineering properties like hydraulic conductivity, strength, and slope stability of varied soil types. This study aims at evaluating the engineering characteristics of gypseous soil treated with xanthan gum biopolymer. The tests performed on three types of gypseous soil with various gypsum contents and different properties. Gypseous soils were mixed with various contents of xanthan gum with a percentage of 2, 4, and 6. The compaction results indicated that xanthan gum decreases the maximum dry density and increases the optimum moisture content. The treated gypseous soils exhibited a low collapse potential by more than 30% – 45% with xanthan gum. The direct shear results of biopolymer treated soils showed significant shear strength gains. The results of the current study imply xanthan gum biopolymer improvement as an environmentally friendly method to improve the engineering properties of gypseous soil.