Durability of Concrete

尽管混凝土技术有所发展，但极端环境下的混凝土仍在过早退化。在某种程度上，这是由于在使用新材料时没有对潜在影响进行充分的评估，或由于使用了不适当的规格或施工方法，但也由于缺乏对影响耐久性的所有因素的了解。水泥浆体基质和膏体-骨料界面区域的孔隙结构和由此产生的流体渗透阻力决定了混凝土对大多数破坏原因的耐久性。具体来说，有四个主要的研究重点：(1)更好地表征孔隙结构、流体进入机制和改进氯离子环境下混凝土使用寿命的预测；(2)改进碱-硅反应的预测；(3)开发混凝土抵抗不同硫酸盐侵蚀机制的新方法；(4)降低早期非结构性开裂的风险。

In spite of developments in concrete technology, concrete in extreme environments continues to prematurely deteriorate. In part this results from utilization of new materials without adequate evaluation of potential impacts, or from use of inadequate specifications or construction methods, but it also results from a lack of understanding of all the factors which influence durability. The pore structure and resultant fluid penetration resistance of the cement paste matrix and paste-aggregate interfacial regions govern the durability of concrete to most causes of distress. Specifically, there are four main areas of research focus: (1) better characterization of pore structure, fluid ingress mechanisms and improving prediction of service life of concretes exposed to chloride environments, (2) improving the prediction of alkali-silica reaction, (3) developing new methodologies for concrete’s resistance to different sulfate attack mechanisms, and (4) reducing the risk of early-age non-structural cracking.