Influence of bacteria on the compressive strength and water absorption of concrete specimens exposed to elevated temperature

In the present laboratory study, cubes of concrete were heated at a temperature of ۶۰۰°C. Then, the efficiency of the microorganism that produces calcium carbonate was examined by conducting compressive strength and water absorption tests on control, heat-damaged and bacterial specimens to evaluate the amount of repairing of damaged samples. The experiment test results revealed that the microorganism Bacillus Sphaericus was very effective in repairing surface cracks in damaged specimens. The compressive strength of specimens treated with the microorganism rose by ۵۲%. In addition, the amount of water absorption of bacterial specimens decreased by ۳۹% compared to damaged samples. Scanning Electronic Microscope (SEM) image of bacterial sample showed that the microorganism produced a considerable amount of calcium carbonate to fill the thermal cracks.

کلیدواژه ها:

concrete ، heat ، bacteria ، crack healing ، water absorption