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Microbiologically-induced calcite-precipitation ( MICP) has been increasingly studied in structural repair including self-healing and extal applications. Among various MICP pathways, enzymatic urea hydrolysis is suggested to be applied as extal repair instead of self-healing. This study comprehensively characterised the enzymatic urea hydrolysis pathway in physical, impermeable, and mechanical rejuvenation of concrete cracks. The visual quality of repaired structures was presented, and the importance of humidity in the remediation of cracks was demonstrated. Moreover, this study investigated the differences in the effectiveness of repair between premixing bacteria with urea and without any premixing. With premixing, there was a conc that the accelerated reactions would precipitate calcite in the shallow spaces of the cracks and impede deeper healing. However, the observed results indicated that neither physical nor impermeable rejuvenation of concrete cracks repair would be detrimentally affected. The results obtained from this study will allow further development in commercialisation since the effectiveness of repair has been confirmed with an improvement in its efficiency.