涂层材料与水工混凝土界面老化机理研究

In the harsh operating environment, hydraulic concrete structures are prone to have a variety of surface damages. Painting surface protective coatings is an effective way to resist external corrosion for the hydraulic concrete structures. And the service results of the coatings are concerned with the interface structure and interface compatibility of the hydraulic concrete/surface protective coating. This study would be basis on the existing interface theories. In the view of the wet hydraulic concretes, the interface would be characterized and measured with scanning electron mocroscopy (SEM), X-ray photoelectron spectroscopy (XPS), the surface wettability, the conformability of coating materials to hydraulic concrete surface cracks et al, and a microstructure model of the hydraulic concrete/surface protective coating interface would be established, and then the relationship between the microstructure model and the adhesive property would be revealed. In addition, indoor accelerated aging tests and outdoor natural aging tests would be done, and then the correlation analysis between the two and the conversion relationship would be studied. Meanwhile, the peeling phenomenon of the hydraulic concrete/surface protective coating interface and the aging of coatings would be explained by the molecular dynamics. And the aging law of the hydraulic concrete/surface protective coating interface and coatings would be revealed and the interfacial microstructure would be further proved. This study would provide a theoretical basis for an effective and long-term protection of hydraulic concretes by coatings.

水工混凝土结构在苛刻的服役环境下，易出现多种表面破坏。表面防护涂层是提高水工混凝土结构抵御外界侵蚀能力的有效方法，其服役效果与水工混凝土/表面防护涂层的界面微结构和粘接性能有主要关系。本项目拟以已有的界面理论为基础，针对水工混凝土的潮湿特质，通过界面的SEM、XPS等微观形貌结构表征以及表面浸润性、涂层材料对水工混凝土的表面裂缝追随性等物化测试，建立水工混凝土/表面防护涂层界面微结构模型，揭示其与粘接性能的关系。进行室内加速老化和室外自然老化试验，分析两者相关性，建立换算公式，并从分子动力学角度解释水工混凝土/表面防护涂层界面剥离和涂层的老化现象，揭示其老化规律，进一步完善界面微结构模型，为涂层材料更加长久有效地保护水工混凝土提供理论依据。

水工混凝土表面防护涂层材料在苛刻的服役环境中易发生破坏，其服役效果与水工混凝土/表面防护涂层的界面微结构和粘接性能有主要关系。本项目设计了一套双层高耐候聚脲复合涂层材料体系，考察了涂层厚度等因素对界面粘接特性的影响，研究了界面特性与宏观抗渗性能的关系，改善了界面粘接性能，由此指导设计出了高耐候聚脲保温涂层材料系统，并研发了高耐候环氧抗冲磨涂层材料。完成了冻融循环、紫外辐射、氙灯辐射、热空气、氙灯辐射—热空气双因素、冻融—紫外辐射双因素等多种室内加速老化试验，揭示了不同老化条件下水工混凝土/表面防护涂层界面的老化规律，探明了界面微结构、界面性能与材料宏观性能三者之间的关系。研究了水工混凝土表面防护涂层在拉萨、厦门、武汉等不同水文气候条件下的室外自然老化情况以及水工混凝土/表面防护涂层界面室外老化规律。研发的防护涂层材料在藏木水电站和满拉水利枢纽进行了工程应用，考察了防护涂层材料在实际服役过程中与水工混凝土的粘接情况。本项目研究成果为进一步实现材料优选和工艺优化提供了理论依据。