INVESTIGATE INFLUENCE OF SOME CULTURE CONDITIONS OF Oceanobacillus sp. ON CALCITE PRECIPITATION AND CONCRETE BINDING ABILITY

Abstract

This study was conducted to determine the effect of the environmental factors on calcium carbonate precipitation of Oceanobacillus sp. and their self-healing ability on cracked concrete. The ability to precipitate calcite of Oceanobacillus sp. was assessed through the CaCO3 quantification in the improved urea medium with individual factors changing such as Ca2+ sources and concentration of Ca2+. The results showed that CaCl2 was the best Ca2+ source for calcite precipitation, the order environmental factors of 50 g/L CaCl2 was suitable condition for calcite precipitation with the highest CaCO3 concentration of 52,05 mg/mL determined in the production medium. In another experiment, the cracked concrete bar samples that were supplemented with 1010 CFU/mL Oceanobacillus sp. bacteria showed the self-healing capability after 10 days immersed in water. These results provided the exciting possibility that Oceanobacillus sp. could be applied in many fields due to their ability of inducing calcite precipitation, especially in the field of building materials and biological concrete.