Characterisation of Bacteria⁃Based Concrete Crack Rejuvenation by Externally Applied Repair  

作　　者：Jie Yuan Xin Chen Mohamed Alazhari Bo Yang Guorong Zhang 

机构地区：[1]School of Transportation Science and Engineering,Harbin Institute of Technology,Harbin 150090,China [2]State Key Laboratory of Safety and Health for In-Service Long Span Bridges,JSTI Group,Nanjing 210019,China [3]BRE Centre for Innovative Construction Materials,University of Bath,Bath BA27AY,UK

出　　处：《Journal of Harbin Institute of Technology(New Series)》2020年第4期20-30,共11页哈尔滨工业大学学报（英文版）

基　　金：Sponsored by the National Natural Science Foundation of China(Grant No.51278157).

摘　　要：Microbiologically⁃induced calcite⁃precipitation(MICP)has been increasingly studied in structural repair including self⁃healing and external applications.Among various MICP pathways,enzymatic urea hydrolysis is suggested to be applied as external 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 concern 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.

关 键 词：concrete crack REJUVENATION BACTERIA repair agent relative humidity IMPERMEABILITY chloride penetration flexural strength 

分 类 号：TU578[建筑科学—建筑技术科学]