基于AH3相协同调控的硫铝酸盐水泥基海工材料性能优化机理

硫铝酸盐水泥因其本体良好的抗海水侵蚀性、胶凝性、抗渗性和抗冻融性等，已成为一种极具潜力的海工混凝土用胶凝材料，且迎来重大历史发展机遇。但其科学理论体系尚不系统；而基于水化产物的组成和结构，设计与提升宏观性能，是推动该水泥应用的迫切需求。申请人前期研究发现该水泥的关键水化产物-铝凝胶（AH3相）可显著地改善孔结构和力学性能。本项目拟使用碳酸化-温度协同调控方法，提高AH3相的含量，优化AH3相的微纳结构；揭示碳酸化-温度在AH3相调控中的协同效应；量化AH3相的含量，探索AH3相尺寸、Al-O配位、离子积、硬度与模量、晶面间距等微纳结构的衍变；阐明AH3相含量与微纳结构变化对宏观力学性能和耐久性的影响机理；确定AH3相的最优含量与微纳结构，提出基于AH3相调控的硫铝酸盐水泥基海工材料性能优化方法。项目可丰富硫铝酸盐水泥的科学理论体系，推动硫铝酸盐水泥在海工领域的应用，促进混凝土行业的碳减排。

Calcium sulfoaluminate (CSA) cements exhibit excellent seawater corrosion resistance, cementitious property, water impermeability, freeze-thaw resistance, etc. CSA cements has been a type of significantly potential cementitious materials used for marine engineering concrete, and their historic development opportunity is coming. However, their current scientific theories are inadequate. The performances of CSA cements can be designed and improved based on the composition and structure of hydration products, which contributes greatly to promoting the application of CSA cements. The applicant has found that the AH3 phase, as a main hydration product of CSA cements, can significantly improve pore structure and mechanical properties. In this work, the synergistic method of carbonation and temperature will be used for increasing the AH3 content and optimizing the AH3 micro/nanostructure. The synergistic effect of carbonation and temperature will be revealed. The AH3 content will be quantified after the synergistic control process. This work will investigate the evolution of the AH3 micro/nanostructure regarding its crystal size, particle size, Al-O coordination, ion activity product, indentation hardness and modulus, interplanar spacing, etc. This work will also illuminate the influence mechanism of the content and micro/nanostructural evolution of the AH3 phase on the mechanical properties and durability. The most optimal content and micro/nanostructure of the AH3 phase will be determined, and the performance optimization of CSA cements-based marine engineering materials will be proposed based on the control of the AH3 phase. The findings will be beneficial to the scientific theories of CSA cements, better promote the application of CSA cements in the marine engineering, and promote the carbon reduction of the concrete industry.