%0 Journal Article
%A LI Yang
%A ZHANG Hui
%A JIANG Ke
%A YUAN Jun
%A YIN Hai-bo
%T Influence of K<sub>2</sub>O/Na<sub>2</sub>O on Early-age Shrinkage and Cracking of Different Cement-based Materials
%D 2022
%R 10.11988/ckyyb.20210585
%J Journal of Changjiang River Scientific Research Institute
%P 124-130
%V 39
%N 9
%X The total alkali content of low heat Portland cement, medium heat Portland cement and ordinary Portland cement were adjusted to 1.2% by adding Na<sub>2</sub>SO<sub>4</sub> and K<sub>2</sub>SO<sub>4</sub> respectively, in which the K<sub>2</sub>O/Na<sub>2</sub>O (by weight) were in the range of 0.4-13.7. The influence of alkali of different K<sub>2</sub>O/Na<sub>2</sub>O on shrinkage properties and cracking properties of cement-based materials were explored. Besides, with the help of microcalorimetry, scanning electron microscopy and energy dispersive spectroscopy, the influence mechanism of alkali of different K<sub>2</sub>O/Na<sub>2</sub>O on shrinkage properties and cracking properties of cement-based materials was revealed. The results show that with the increase of K<sub>2</sub>O/Na<sub>2</sub>O, the autogenous shrinkage and drying shrinkage of low-heat and ordinary Portland cement intensified, while those of medium-heat cemet first decreased and then increased, and the cracking sensitivity of different cement-based materials always increased. The difference in shrinkage properties caused by K<sub>2</sub>O/Na<sub>2</sub>O was related to the hydration process of cement-based materials. The difference in cracking sensitivity was not only related to shrinkage properties, but also affected by the morphology of hydrated calcium silicate (C-S-H), calcium hydroxide (CH) and the enrichment of elements in the interfacial transition zone (ITZ).
%U http://ckyyb.crsri.cn/EN/10.11988/ckyyb.20210585