Autor: |
Gu Dezhen, Xiong Dayu, Lu Zhang |
Zdroj: |
Journal of the American Concrete Institute; Sep/Oct1982, Vol. 79 Issue 5, p378-386, 9p |
Abstrakt: |
A qualitative examination was made employing infrared spectroscopy, x-ray diffraction method, and differential thermal analysis (DTA), and the amount of hydration water was measured. The hydration process of portland cement was found to be divided into three stages, and the reaction kinetic equations were derived. The main factors affecting each stage of the hydration process were studied. Crystallization process and pore structure were investigated by employing a scanning electron microscope (SEM) and measuring pore distribution. The water-reducing admixtures retard crystallization and improve pore distribution. It was recognized that the effect of admixtures on the hydration process is not due to chemical reaction. A model is suggested for studying the effect of admixtures on the hydration process of cement. [ABSTRACT FROM AUTHOR] |
Databáze: |
Complementary Index |
Externí odkaz: |
|