DEVELOPMENT OF A CRACK REPAIR METHOD USING YEASTINDUCED CALCIUM CARBONATE PRECIPITATION

Abstract

Although many examples of water leakages are observed between the high column of the
bridge and the deck, the gaps in between them are not recognized as degradation. However, if water leaks from
the gap, deterioration of the reinforced concrete becomes faster than expected, so even though this is not an
urgent matter, some inexpensive repairs would be necessary. In this study, the applicability of bio-grout using
microbial metabolism for crack repairs was investigated. Bio-grout is a repair material using microbial
metabolism, mainly based on water. Therefore, bio-grout is expected to penetrate cracks more easily due to a
capillary tension that is quite different from conventional inorganic or organic grout. Therefore, it is
unnecessary to press fit the grout into cracks, and this grout is environmentally friendly. This study examined
the mixture proportion of the bio-grout used to produce a significant amount of calcium carbonate. Further, the
precipitation amount of calcium carbonate was investigated via sedimentation analysis using a geochemical
code. The simulation model based on the geochemical code successfully reproduced, the precipitation amount
of calcium carbonate with reasonable precision.