Development of a novel compressed tablet-based bacterial agent for self-healing cementitious material. (May 2022)

• Record Type: Journal Article
• Authors: Son, Yongjun; Min, Jihyeon; Jang, Indong; Yi, Chongku; Park, Woojun
• Is Part Of: Cement & concrete composites. Volume 129(2022)
• Publication Date: 2022-05
• Subjects: Bio-concrete -- Agricultural by-product -- Sporulation -- Encapsulation -- Compression-type -- Tablet; Composite-reinforced concrete -- Periodicals; Concrete -- Periodicals; Composite materials -- Periodicals; Composites de ciment -- Périodiques; Béton -- Périodiques; Composites -- Périodiques; Béton léger -- Périodiques; Cement composites; Composite materials; Composite-reinforced concrete; Concrete; Lightweight concrete; Periodicals; Electronic journals; 620.135
• DOI: 10.1016/j.cemconcomp.2022.104514
• Languages: English
• ISSNs: 0958-9465

Abstract

Abstract: A novel bacterial carrier consisting of microcrystalline cellulose (MCC) tablets was developed to encapsulate spores and has 3.0 ± 0.5 × 10 11 spores per dried gram, which could improve the self-healing efficiency of bacterial agents. The alkaline-resistant and spore-forming bacteria Lysinibacillus boronitolerans YS11 and Bacillus miscanthi AK13 could fill microcracks with precipitated calcium carbonate in harsh cement conditions. The MICP-capable bacteria in the tablets cured the microcracks within 7 days. The calcium carbonate on the cracks was identified via scanning electron microscopy and X-ray diffractometry, validating the MICP performance and bacterial viability. Constituting only 3% of the cement mass, the MCC-tablet allowed repairing of micro-cracks. The water permeability of mortar specimens mixed with MCC tablets steadily reduced with increasing curing ages, with crack repair rates of up to 91.1% within 28 days. Our study proved that the MCC tablets developed herein are effective carriers of bacterial spores and could thus be used for the development of self-healing cementitious material. Highlights: Microcrystalline cellulose (MCC)-based tablets were manufactured for bio-concrete. Compressed MCC-tablets were able to protect bacterial spores in mortar specimens. MCC-tablets harboring spores could repair cracks by precipitating calcium carbonate. Self-healing performance of bio-concrete could be improved by our novel MCC-tablet.