The Optimisation Analysis of Sand-Clay Mixtures Stabilised with Xanthan Gum Biopolymers

Sand–clay mixtures can be encountered in both natural soils (e.g., residual soils, clay deposits and clinosols) artificial fills. The method of utilising biopolymers ground improvement for sand–clay has emerged recently. However, a full understanding the strengthening effect biopolymer-treated not yet been achieved due to limited number relevant studies. In this study, xanthan gum (XG), as one eco-friendly biopolymers, was used treat reconstituted that had various compositions related (or sand) content type (kaolin bentonite). A series laboratory unconfined compression strength (UCS) tests were conducted probe performances XG-treated from two aspects, i.e., optimum treatment conditions XG initial moisture content) achieve maximum efficiency with different compositions. experimental results indicated decreased sand increased. content, which also increasing remained approximately 3.75% all sand–kaolin 5.75% sand–bentonite if calculated based on fraction. While untreated comparable UCS values, seemed have better improved mechanical higher ionic hydrogen) bonds low-swelling properties compared bentonite. deformation modulus positively UCS. variation stiffness each condition increased elevated sand-kaolin sand-bentonite mixtures. An increment proportion heterogeneous composite formed by irregular particles conglomerated XG–clay matrix total soil might responsible phenomenon.