Stabilization of Soil Using Geoploymer and Biopolymer

Abstract

As stabilization of soil improves its  engineering properties, chemical and mechanical  stabilization processes are in use. In the present study two  difficult soils; expansive soil and dispersive soil are  stabilized with geopolymer and biopolymer. Sodium based  alkaline activators and fly ash as an additive are used as  geopolymers and Xanthan gum and Guar gum are used as  biopolymers. The effectiveness of geopolymer is studied in  terms of unconfined compressive strength (UCS),  differential free swelling (DFS), swelling pressure (SP),  durability and dispersion tests. The swelling pressure got  reduced by 97.14% finally with addition of 40% fly ash and  15% bentonite. The dispersion test showed bentonite to be  an extremely dispersive soil, whose dispersiveness is  controlled by addition of alkali activated fly ash. From UCS  and durability test it is observed that bentonite added with  40% fly ash and 10% solution gave better results. The  effectiveness of biopolymer is studied based on UCS tests on  dispersive soil and pond ash at their moisture content. For  dispersive soil, durability, dispersion and DFS tests are also  done. It is observed that dispersive soil and pond ash mixed  with various percentages of Xanthan gum and Guar gum are  not dispersive and are more durable than ordinary bottom ash  and dispersive soil samples.