Microbial mineralization in cementitious materials: Impact on self-healing and durability

这里描述的研究建议调查生物矿化的水泥系统。该项目首先侧重于选择最合适的微生物，包括对碱性环境的良好抵抗力。这些实验将在水泥悬浮液中进行。在下一步中，这些微生物对自愈合能力的影响，以及对水泥样品的耐久性进行了研究，在硬化水泥浆和砂浆。我们与东京海洋科技大学的日本合作伙伴合作，使用两种不同的调查技术进行微生物的选择。在接下来的步骤中，砂浆和硬化水泥浆样品与四种不同的水泥类型的自愈能力，分析使用光学显微镜，以及通过相分析和孔隙率的微观结构的表征。该分析步骤包括机械性能测试。此外，使用选择的恶劣环境，包括耐冻融性和暴露在酸性和盐溶液中，研究了样品的耐久性。关于不同类型的微生物对裂缝愈合的适用性的结论是预期的，从而通过提高耐久性对可持续性做出贡献。

The here described research proposal investigates the biogenic mineralisation of cementitious systems. The project focusses firstly on the selection of the most suitable microbes, which includes a good resistance against alkaline environments. These experiments will be conducted in cementitious suspensions. In the next step, the impact these microbes have on self-healing abilities as well as on the durability of cementitious samples is investigated in hardened cement pastes and in mortars. In cooperation with our Japanese partners from the Tokyo University of Marine Science and Technology, a selection of microbes is performed using two separate investigation techniques. In the next step, the self-healing abilities of mortar and hardened cement paste samples with four different cement types, are analyzed using optical microscopy as well as a characterization of microstructure through phase analysis and porosity. Included in this analytical step, is the testing of mechanical properties. Additionally, the durability of samples in investigated using a selection of harsh environments including freeze-thaw resistance and exposition in acidic and salt solutions. Conclusions regarding the suitability of different microbe types for crack-healing are expected, resulting in a contribution to sustainability through improved durability.