{"title":"Effectiveness of Biological Mortars with Bacterial Glycocalyx on Service Life of Concrete Structures Exposed to Salt Attack","authors":"","doi":"10.1186/s40069-023-00648-7","DOIUrl":null,"url":null,"abstract":"<h3>Abstract</h3> <p>This study investigated the effectiveness and limitations of newly developed biological mortars regarding chloride ion diffusion resistance. Through several tests on the glycocalyx production capacity and growth potentials of bacteria cells under marine environments, <em>Bacillus licheniformis</em> was isolated and immobilized in the expanded vermiculites together with a bacterial culture medium for producing biological mortars. The chloride ion diffusion coefficient of the mortars up to 91 days was determined through natural diffusion cell tests. Subsequently, the service life of RC structure repaired with biological mortars under chloride attack was evaluated considering multilayer theory and time-dependent diffusion. The addition of expanded vermiculites immobilizing <em>Bacillus licheniformis</em> significantly reduced the chloride ion diffusion coefficient. When its addition increased from 10 to 30%, the chloride ion diffusion coefficient decreased by 50–90% compared to that of mortars without bacteria. The service life of reinforced concrete structures repaired with biological mortars containing 30% expanded vermiculite concentration and thickness of 50 mm was evaluated to be six times longer than that of repaired with conventional mortar. Overall, this novel approach holds significant potential in addressing the salt-induced deterioration challenges faced by RC structures.</p>","PeriodicalId":13832,"journal":{"name":"International Journal of Concrete Structures and Materials","volume":null,"pages":null},"PeriodicalIF":3.6000,"publicationDate":"2024-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"International Journal of Concrete Structures and Materials","FirstCategoryId":"5","ListUrlMain":"https://doi.org/10.1186/s40069-023-00648-7","RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CONSTRUCTION & BUILDING TECHNOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
This study investigated the effectiveness and limitations of newly developed biological mortars regarding chloride ion diffusion resistance. Through several tests on the glycocalyx production capacity and growth potentials of bacteria cells under marine environments, Bacillus licheniformis was isolated and immobilized in the expanded vermiculites together with a bacterial culture medium for producing biological mortars. The chloride ion diffusion coefficient of the mortars up to 91 days was determined through natural diffusion cell tests. Subsequently, the service life of RC structure repaired with biological mortars under chloride attack was evaluated considering multilayer theory and time-dependent diffusion. The addition of expanded vermiculites immobilizing Bacillus licheniformis significantly reduced the chloride ion diffusion coefficient. When its addition increased from 10 to 30%, the chloride ion diffusion coefficient decreased by 50–90% compared to that of mortars without bacteria. The service life of reinforced concrete structures repaired with biological mortars containing 30% expanded vermiculite concentration and thickness of 50 mm was evaluated to be six times longer than that of repaired with conventional mortar. Overall, this novel approach holds significant potential in addressing the salt-induced deterioration challenges faced by RC structures.
期刊介绍:
The International Journal of Concrete Structures and Materials (IJCSM) provides a forum targeted for engineers and scientists around the globe to present and discuss various topics related to concrete, concrete structures and other applied materials incorporating cement cementitious binder, and polymer or fiber in conjunction with concrete. These forums give participants an opportunity to contribute their knowledge for the advancement of society. Topics include, but are not limited to, research results on
Properties and performance of concrete and concrete structures
Advanced and improved experimental techniques
Latest modelling methods
Possible improvement and enhancement of concrete properties
Structural and microstructural characterization
Concrete applications
Fiber reinforced concrete technology
Concrete waste management.