基于铁相对侵蚀介质阻滞与吸附机制的水泥基材料劣化动力学研究

The construction and service safety of ocean engineering and hydraulic project is the guarantee of national marine development strategy energy development strategy. However, The phenomenon of premature deterioration of marine and hydraulic concrete is outstanding under corrosion environment. It was found that the shrinkage and corrosion resistance of cement-based materials would be improved by ferrite, and the chloride ion was adsorption by hydrated products. But the mechanism of block and adsorption by ferrite was not settled. Therefore, in this study, the transport mechanism of different chemical compound in high ferrite cement-based materials will be studied and the coupling effect between chemical reaction and diffusion would be analyzed. By constructing the model of media migration, the mechanism of block and adsorption by ferrite under different erosion conditions could be revealed. The effect of the change in microstructure of high ferrite cement-based materials on mass transport, chemical attack reaction and deterioration mechanism would be investigated, based on which the correlation between microstructure and deterioration mechanism is established. The mechanism of active admixture on high ferrite cement-based materials could be revealed. The change of different hydration products, pore structures and the formation of chemical attack reaction products, the thermodynamic conditions of chemical attack damage will be discussed after track testing, which contributes to revealing the kinetic mechanism of the deterioration. The mathematic model and of chemical attack deterioration under the conditions of various factors will be derived, and the life prediction mechanism is established, which is a theoretical basis for improving the service performance of cement-based materials under harsh environment.

海洋工程、水利工程的建设与服役安全是保障国家海洋大开发战略、能源发展战略实施的重要支撑。在侵蚀环境下，海工、水工混凝土过早劣化破坏现象突出。水泥中铁相不仅可以提高抗蚀性能，且水化相具有较强氯离子吸附能力，目前缺乏不同组成、结构的铁相对侵蚀离子吸附阻滞机制及其劣化机理的系统研究。本项目通过研究铁相的水化产物与侵蚀介质的相关性，基于Fick扩散定律与化学反应的耦合关系，揭示铁相对侵蚀介质的阻滞吸附机制；通过分析不同侵蚀条件下高铁相水泥基材料宏观力学特征差异对微观结构的表征，建立宏观力学性能与微结构之间的定量关系；探明活性掺合料在高铁相水泥基材料中的作用机制；跟踪高铁相水泥基材料的侵蚀劣化进程，分析水化产物的孔结构特征与演变规律，结合水化动力学理论，提出高铁水泥基材料侵蚀劣化动力学模型并建立寿命预测机制，实现材料性能的可设计与调控，为提高水泥基材料在侵蚀环境下的服役性能提供理论依据。

海洋工程、水利工程的建设与服役安全是保障国家海洋大开发战略、能源发展战略实施的重要支撑。但是，在侵蚀环境下，海工、水工混凝土过早劣化破坏现象突出。水泥中铁相不仅可以提高抗蚀性能，且水化相具有较强氯离子吸附能力，目前缺乏不同组成、结构的铁相对侵蚀离子吸附阻滞机制及其劣化机理的系统研究。本项目通过研究铁相的水化产物与侵蚀介质的相关性，揭示了铁相对侵蚀介质的阻滞吸附机制；通过分析不同侵蚀条件下高铁相水泥基材料宏观力学特征差异对微观结构的表征，建立了宏观力学性能与微结构之间的定量关系；探明了活性掺合料在高铁相水泥基材料中的作用机制；研究了活化后高铁相水泥基材料微结构与铁相活化机制的响应关系，构建了不同化学侵蚀条件下高铁相水泥基材料侵蚀劣化模型。揭示了内驱动下铁相的活化改性机制；研究了活化后高铁相水泥基材料微结构与铁相活化机制的响应关系，优化铁相的结构，调配水泥基材料的矿物组成，实现铁相的最优化作用。从本质上为海工水泥基材料寿命的延长提供理论指导。