Application of modified-alginate encapsulated carbonate producing bacteria in concrete: a promising strategy for crack self-healing.
Application of modified-alginate encapsulated carbonate producing bacteria in concrete: a promising strategy for crack self-healing.
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DOI：
10.3389/fmicb.2015.01088
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发表时间：
2015
影响因子：
5.2
通讯作者：
De Belie N
中科院分区：
文献类型：
--
作者：
Wang J;Mignon A;Snoeck D;Wiktor V;Van Vliergerghe S;Boon N;De Belie N
自愈合混凝土在降低混凝土维护和修复成本方面具有很大的优势，因为裂缝是在没有任何人工干预的情况下自动修复的。本研究对碳酸盐沉淀菌球形芽孢杆菌的应用进行了探索。针对混凝土的苛刻条件，首先将球形芽胞杆菌孢子包裹在改性海藻酸盐水凝胶(AM-H)中，证明该水凝胶与细菌和混凝土具有良好的相容性，对细菌活性和混凝土强度的影响。实验结果表明，包埋后的孢子仍能存活。包裹的孢子可以在水凝胶基质中/在水凝胶基质上沉淀大量的碳酸钙(重量约为70%)。将包裹的球形芽胞杆菌孢子添加到砂浆样品中，通过模拟裂缝表面的耗氧量来证明细菌的原位活性。而添加游离孢子的样品则没有耗氧量。这表明水凝胶对混凝土中的孢子具有有效的保护作用。综上所述，AM-H包裹的碳酸盐沉淀菌在混凝土裂缝自愈合方面具有很大的潜力。
Self-healing concrete holds promising benefits to reduce the cost for concrete maintenance and repair as cracks are autonomously repaired without any human intervention. In this study, the application of a carbonate precipitating bacterium Bacillus sphaericus was explored. Regarding the harsh condition in concrete, B. sphaericus spores were first encapsulated into a modified-alginate based hydrogel (AM-H) which was proven to have a good compatibility with the bacteria and concrete regarding the influence on bacterial viability and concrete strength. Experimental results show that the spores were still viable after encapsulation. Encapsulated spores can precipitate a large amount of CaCO3 in/on the hydrogel matrix (around 70% by weight). Encapsulated B. sphaericus spores were added into mortar specimens and bacterial in situ activity was demonstrated by the oxygen consumption on the mimicked crack surface. While specimens with free spores added showed no oxygen consumption. This indicates the efficient protection of the hydrogel for spores in concrete. To conclude, the AM-H encapsulated carbonate precipitating bacteria have great potential to be used for crack self-healing in concrete applications.