Yamei Cai , Xiaohong Zhu , Keke Sun , Kesheng Yin , Dongxing Xuan , Chi Sun Poon
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引用次数: 0
Abstract
This study compared the sulphate resistance of deionized water (DI)- and seawater (SW)-mixed cementitious materials based mainly on microstructural observations. The results show that, after a 450-day exposure to 50 g/L Na2SO4 solution, there was an increase in the mean chain length and polymerization degree of the remaining silicate chains in C-S-H gel for both DI- and SW-mixed pastes at a depth of 0–2 mm from the exposed surface. Notably, the Ca leaching of C-S-H gel in the SW-mixed paste at depths larger than 0.3 mm was slightly less than that in the DI-mixed one, despite the Ca leaching in both samples was comparable at a depth of 0.1 mm. For the aluminate phase, the mass loss and length change of the SW-mixed C3A mortar were lower than that of the DI-mixed C3A mortar, after immersing in 50 g/L Na2SO4 solution at different times. It seemed that more expansive product can be accommodated in the SW-mixed C3A matrix. Consequently, fewer cracks deposited by gypsum were observed in SW-mixed paste than in DI-mixed paste. The above were responsible for relatively less compressive strength loss of the SW-mixed mortars suffering from sulphate attack for 450 d.
期刊介绍:
Cement & concrete composites focuses on advancements in cement-concrete composite technology and the production, use, and performance of cement-based construction materials. It covers a wide range of materials, including fiber-reinforced composites, polymer composites, ferrocement, and those incorporating special aggregates or waste materials. Major themes include microstructure, material properties, testing, durability, mechanics, modeling, design, fabrication, and practical applications. The journal welcomes papers on structural behavior, field studies, repair and maintenance, serviceability, and sustainability. It aims to enhance understanding, provide a platform for unconventional materials, promote low-cost energy-saving materials, and bridge the gap between materials science, engineering, and construction. Special issues on emerging topics are also published to encourage collaboration between materials scientists, engineers, designers, and fabricators.