García Calvo José Luis, Sánchez Moreno Mercedes, Alonso Alonso María Cruz, Hidalgo López Ana, García Olmo Juan
Institute for Construction Sciences Eduardo Torroja, IETcc-CSIC, Serrano Galvache 4, Madrid 28033, Spain.
Programs Office, CSIC Delegation in Andalusia, Seville 41013, Spain.
Materials (Basel). 2013 Jun 18;6(6):2508-2521. doi: 10.3390/ma6062508.
Low-pH cements are designed to be used in underground repositories for high level waste. When they are based on Ordinary Portland Cements (OPC), high mineral admixture contents must be used which significantly modify their microstructure properties and performance. This paper evaluates the microstructure evolution of low-pH cement pastes based on OPC plus silica fume and/or fly ashes, using Mid-Infrared and Near-Infrared spectroscopy to detect cement pastes mainly composed of high polymerized C-A-S-H gels with low C/S ratios. In addition, the lower pore solution pH of these special cementitious materials have been monitored with embedded metallic sensors. Besides, as the use of reinforced concrete can be required in underground repositories, the influence of low-pH cementitious materials on steel reinforcement corrosion was analysed. Due to their lower pore solution pH and their different pore solution chemical composition a clear influence on steel reinforcement corrosion was detected.
低pH值水泥旨在用于高放废物的地下储存库。当它们以普通硅酸盐水泥（OPC）为基础时，必须使用高矿物掺合料含量，这会显著改变其微观结构性能和性能。本文评估了基于OPC加硅灰和/或粉煤灰的低pH值水泥浆体的微观结构演变，使用中红外和近红外光谱检测主要由低C/S比的高度聚合C-A-S-H凝胶组成的水泥浆体。此外，这些特殊胶凝材料较低的孔隙溶液pH值已通过嵌入式金属传感器进行监测。此外，由于地下储存库可能需要使用钢筋混凝土，因此分析了低pH值胶凝材料对钢筋腐蚀的影响。由于其较低的孔隙溶液pH值和不同的孔隙溶液化学成分，检测到对钢筋腐蚀有明显影响。
