Study of the Microstructure Evolution of Low-pH Cements Based on Ordinary Portland Cement (OPC) by Mid- and Near-Infrared Spectroscopy, and Their Influence on Corrosion of Steel Reinforcement

Materials

José Luis Garc໚ Calvo¹  Mercedes Sánchez Moreno¹  Mar໚ Cruz Alonso Alonso¹  Ana Hidalgo López² 

[1] Institute for Construction Sciences Eduardo Torroja, IETcc-CSIC, Serrano Galvache 4, Madrid 28033, Spain; E-Mails:;Programs Office, CSIC Delegation in Andalusia, Seville 41013, Spain; E-Mail:

关键词: low-pH cements;    hydration;    microstructure;    pH sensors;    corrosion of steel reinforcements;   

DOI  :  10.3390/ma6062508

来源: mdpi

【 摘 要 】

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.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland.