Preliminary study on use of biopolymers in earthen construction.

Abstract

Biopolymers are known to achieve significant soil stabilisation when working with small quan-tities. There have been studies understanding their effects on permeability, strength, compressibility and dura-bility, however, there are few studies exploring their potential as stabilisers in earthen construction. An earth-en material is typically stabilised with energy consuming stabilisers like cement to enhance durability, and biopolymers could be viable green alternatives. Based on recently established understanding of mechanical behaviour of biopolymer-treated earthen construction materials, the preliminary study described here was un-dertaken to understand their effects on durability. In this study, two biopolymers, namely guar and xanthan gums, were used as stabilisers to treat earthen construction materials and tested for their durability perfor-mance through erosional and immersion tests. The treated materials performed satisfactorily in erosional tests, while only xanthan gum treated material performed well in immersion tests. Elementary X-Ray Computed Tomography scans were undertaken on biopolymer treated materials at 7 and 28 days after manufacture. It was observed that there was particle re-arrangement from 7 to 28 days and this was more evident for guar gum treated soil.