Improvement of Concrete Materials by Bacterial-Mediated Precipitation
Microbial carbonate precipitation had been proposed as alternative technique for improvement in concrete materials. Laboratory experiments were conducted by bacterially mediated carbonate deposition on the surface and subsurface of concrete specimens. The crystal phase, morphology and growth of the crystal deposited on specimens as well as the efficiency of bonding and protection were analyzed by means of X-ray diffraction (XRD), scanning electron microscope (SEM), and ultrasonic test. Water absorption and the resistance of carbonation of concrete were analyzed by water absorptivity test and concrete accelerated carbonation test, respectively. Results show that phases of crystal are calcite and vaterite. The crystals are deposited uniformly on the surface of specimens. Biodeposotion effectively reduces capillary water uptake and carbonation rate constant.
Shiquan Liu and Min Zuo
P. H. Li and W. J. Qu, "Improvement of Concrete Materials by Bacterial-Mediated Precipitation", Advanced Materials Research, Vols. 306-307, pp. 455-458, 2011