Study on Improvement of Soil Behaviour by Bio-Stabilsation Method

Background/Objectives: In India the increase in population and industrialisation, there is a much need for the soil to be used for various activities. There is a need to improve the properties of soil, if the soil at any particular locality is unsuited, wholly or partially selected for the construction. With increasing awareness of environmental issues, there has been a remarkable shift toward “green” and sustainable technologies. In view of these attempt is made to study the new sustainable method of biogeochemical techniques to improve the soil properties. Methods: In this work test for the Unconfined Compressive Strength (UCS) for soils were conducted as per IS to know variation in strength characteristics with the addition of two bacteria namely Acetobacter and Bacillus of different incubation periods and curing periods. For the same soil samples, the free swell index values were also determined to know the effect of addition of bacteria by stabilisation. Findings: The UCC test results for the soil samples treated with bacteria showed an increase in strength of soil with the increase in age of bacteria. The increase in Unconfined Compressive Strength (UCS) value at 60 day curing period is about 175% for soil treated with Acetobacter and 520% for Bacillus. Swelling characteristics also reduced by the treatment with Acetobacter and Bacillus bacteria. Improvement/Applications: Biostabilisation with bacteria proved the increase in strength and decrease in swell it can be used as an innovative stabiliser for stabilising problematic soils, which is cost-effective, non intrusive, low energy demanding and ecofriendly.