The Feasibility of Waterproof Microcapsule System for Bacteria-Based Self-Healing Cementitious Material
In this study, a waterproof material was used to fabricate microcapsule by interfacial curing reaction to encapsulate an alkaliphilic spore-forming bacterium. The technical feasibility of encapsulated spores and the influence of three kinds of curing agent on the calcium precipitation activity (CPA) of the bacterium were studied. Furthermore, micromorphology of microcapsules was observed by Scanning Electron Microscopy (SEM). Afterwards, the thermal stability and thermolysis temperature were determined by TGA thermal analyzer. Moreover, the CPA of broken/ unbroken microcapsules was evaluated. In addition, water resistance was evaluated by adding microcapsules in the water for 1, 3, 7, 14, 28, and 56 days. Finally, light microscope was applied to trace the self-healing behavior of encapsulated mineralization bacterium in cement paste specimens. The results showed that compared with unbroken microcapsules, higher CPA was achieved by breaking the microcapsule to release the bacterium, suggesting good protection for the encapsulated spores. Three curing agents showed nearly similar influence on the spores, while KH792 performed relatively better, and thus was used to fabricate microcapsule with the core/shell weight ratio being 1:1. Our results also indicated that ER microcapsules could keep unbroken in the water for 2 months. Compared with the specimens without embedded bacterium, the healed crack area of specimens embedded with bacterial microcapsules was monitored, suggesting effective self-healing of concrete crack can be achieved by introducing encapsulated mineralization microorganisms into concrete structures. Therefore, we put forward that this waterproof epoxy resin microcapsules could be potential for the application of self-healing concrete.
Bing Liu Biqin Dong Ningxu Han Fing Xing Bing Liu Xu Deng Guangmin Zhu
Guangdong Provincial Key Laboratory of Durability for Marine Civil Engineering, Shenzhen Durability School of Transportation and Environmental Science, Shenzhen Institute of Information Technology, Ch College of Life Science, Shenzhen Key Laboratory of Marine Bioresource and Eco-Environmental Science Shenzhen Key Laboratory of Special Functional Materials, College of Materials Science and Engineerin
国际会议
The 5th International Conference on the Durability of Concrete Structures(第五届混凝土结构耐久性国际学术会议)
深圳
英文
251-254
2016-07-01（万方平台首次上网日期，不代表论文的发表时间）