An Experimental Study on the Bio-cementation and Bio-clogging Effect of Bacteria in Improving Weak Dredged Soils

In this study an attempt has been made to improve weak soils. A bacterium, Sporosarcina pasteurii at an optical density of 1.5 along with a cementing solution has been used and unconfined compressive strength (UCS), permeability and California bearing ratio (CBR) tests have been performed on the soil samples. A cementing solution molarity ( CSM ) of 0.5 and 1 has been adopted for this study. The treated samples were cured for 7 and 14 days respectively at two different temperature ranges (5–10 and 18–23 °C). The tests revealed that the UCS increased with curing time and maximum results were noted at 0.5 CSM and 7 days curing. The permeability coefficient decreased whereas the CBR values increased as the CSM increased. The results provided an insight on the capability of microbes in improving weak soils and were in turn supported by scanning electron microscopy and energy dispersive spectroscopy.