Ureolytic-type bacteria has been used to improve the strength of cement mortar by the precipitation of calcium carbonate.In the present study Bacillus sphaericus has been used to improve the properties of cement morta...Ureolytic-type bacteria has been used to improve the strength of cement mortar by the precipitation of calcium carbonate.In the present study Bacillus sphaericus has been used to improve the properties of cement mortar such as setting time,compressive strength and sorptivity.The setting time is found to be unaffected by the presence of bacteria.It is found that compressive strength at both 7-days and 28-days of mortar cube increases with the increase of bacteria concentration.At the optimum bacteria dosage of 107 cells/ml,the average compressive strength increases by 58%(at 7 day)and 23%(at 28 day)over the control specimen.The sorpitivity coefficient decreases as the concentration of bac-terial cells increases.The mineralogy and morphology of the cal-cium carbonate precipitation have been tested by XRD and FESEM.展开更多
文摘Ureolytic-type bacteria has been used to improve the strength of cement mortar by the precipitation of calcium carbonate.In the present study Bacillus sphaericus has been used to improve the properties of cement mortar such as setting time,compressive strength and sorptivity.The setting time is found to be unaffected by the presence of bacteria.It is found that compressive strength at both 7-days and 28-days of mortar cube increases with the increase of bacteria concentration.At the optimum bacteria dosage of 107 cells/ml,the average compressive strength increases by 58%(at 7 day)and 23%(at 28 day)over the control specimen.The sorpitivity coefficient decreases as the concentration of bac-terial cells increases.The mineralogy and morphology of the cal-cium carbonate precipitation have been tested by XRD and FESEM.
