Chemical shrinkage and autogenous shrinkage of hydrating cement paste
β Scribed by Ei-ichi Tazawa; Shingo Miyazawa; Tetsurou Kasai
- Publisher
- Elsevier Science
- Year
- 1995
- Tongue
- English
- Weight
- 325 KB
- Volume
- 25
- Category
- Article
- ISSN
- 0008-8846
No coin nor oath required. For personal study only.
β¦ Synopsis
It is well known that the absolute volume of cement plus water decrease with progressive hydration. In this study, chemical shrinkage of cement was calculated from chemical equation of hydration, it was compared with observed one. Definition of chemical shrinkage and autogenous shrinkage was made and relationship between them was clearly described.
π SIMILAR VOLUMES
After having studied phenomena linked to hydration and self-desiccation, one notes that capillary depression is the main origin of the autogenous shrinkage of hardening cement paste. Based on this mechanism, modelling at macroscopic scale is undertaken for a commonly used cement paste (CPA 55) with
In this paper the authors tried to analyze their drying shrinkage data in terms of the Munich model. They have attributed the shrinkage below 40% RH to a change in the surface free energy (socalled Bangham shrinkage) and the shrinkage above 40% RH to the disjoining pressure. As the authors are propo
Whilst being dried a cement paste is simultaneously subjected to peripherical tensile and radial compressive stresses. This combination may lead to relaxation or cracking. It is a general belief that these macroscopic stresses can be ignored if one uses thin specimens. Fluorescence microscopy of 1.5
On a series of fully hydrated OPC pastes hydrated at two temperatures (20 and 90 Β°C) and on tricalcium silicate pastes hydrated at 20 o the bound water, chemical shrinkage and density of hydrates were determined. Significant differences were found between the compared groups of materials with respec