当前位置: X-MOL 学术Cem. Concr. Res. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Effects of environmental exposure on Portland cement Type IL
Cement and Concrete Research ( IF 10.9 ) Pub Date : 2024-12-24 , DOI: 10.1016/j.cemconres.2024.107775
Rotana Hay, Parham Aghdasi

This study investigates the physico-chemical change in a Type IL cement prehydrated in the natural environment for 7, 14, and 21 days. A focus was made on the reaction kinetics, product formation, and strength development using calorimetry, XRF, QXRD, TGA and compressive testing. It was found that prehydration converted hemihydrate to gypsum and partially transformed the principal cement phases and inherent portlandite into carbonates, thus reducing C3S and C2S while increasing CaCO3 and gypsum. Hydration was slowed down with a delay in the appearance of the aluminate peak and reduction in cumulative heat at 72 h. Consequently, more C3S and C2S remained at an early age. Less ettringite was formed while amorphous phases were initially reduced but promoted later on. A secondary decomposition peak linked to metastable CaCO3 became more prominent in the prehydrated samples. The early-age strength was reduced with the exposure time, but the 28-day strength improved due to the continuing hydration.

中文翻译:


环境暴露对 IL 型波特兰水泥的影响



本研究调查了在自然环境中预水化 7、14 和 21 天的 IL 型水泥的物理化学变化。使用量热法、XRF、QXRD、TGA 和压缩测试,重点研究了反应动力学、产物形成和强度发展。研究发现,预水化将半水合物转化为石膏,并将主要胶结相和固有的硅酸盐部分转化为碳酸盐,从而减少 C3S 和 C2S,同时增加 CaCO3 和石膏。水合作用减慢,铝酸盐峰的出现延迟,72 小时时累积热量减少。因此,更多的 C3S 和 C2S 保留在早期。当无定形相最初被还原但后来得到促进时,形成的钙矾石较少。与亚稳 CaCO3 相关的次级分解峰在预水合样品中变得更加突出。随着暴露时间的增加,早期的强度降低,但由于持续的水合作用,28 天的强度有所提高。
更新日期:2024-12-24
down
wechat
bug