THE ELECTRON MICROSCOPE STUDY OF THE HYDRATION OF CALCIUM SILICATES IN PORTLAND CEMENTS
CALCIUM SILICATE HYDRATES CONSTITUTE THE TOBERMORITIC GEL WHICH IS THE BASIS OF THE BINDING PROPERTIES OF ARTIFICIAL PORTLAND CEMENT PASTES. THEY ARE FORMED OF FOLIACEOUS PARTICLES, MORE OR LESS COILED, VERY SMALL IN SIZE AND EXTREMELY THIN (A FEW DOZEN ANGSTROMS). DIFFICULTIES ARE ENCOUNTERED IN STUDYING RHEM UNDER THE ELECTRON MICROSCOPE, MAINLY DUE TO THEIR SEMI-AMORPHOUS STATE, THEIR VARIABLE, MULTIPLE, OFTEN IMPRECISE MORPHOLOGY AND THE FACT THAT THEY ARE INTIMATELY MIXED WITH THE LIME. OBSERVATIONS MADE DURING THE INITIAL HOURS OF HYDRATION ON SUSPENSIONS AND PASTES OF CALCIUM SILICATES OR PORTLAND CEMENT HAVE SHOWN THAT THE LIME, AND UNDER CERTAIN CONDITIONS THE CALCIUM SILICATE HYDRATE, PASS THROUGH AN AMORPHOW STATE. THE TRANSITION FROM THIS STATE TO THE CRYSTALLINE STATE HAS BEEN ESPECIALLY DEMONSTRATED IN THE CASE OF LIME. THE COHESION IN THE HARDENED PASTES MAY RESULT AT ONE AND THE SAME TIME FROM THE MUTUAL TANGLING AND WRAPPING OF LEAVES OF TOBERMORITIC GEL. THIS IS CONFIRMED BY OBSERVATIONS MADE WITH A STEREOSCAN REFLECTION TYPE ELECTRON MICROSCOPE. IN THE PROPERTIES OF TOBERMORITIC GEL, LIME PLAYS A ROLE WHICH IS CERTANLY IMPORTANT BUT COMPLEX: THIS FACT HAS BEEN UNDERLINED BY THE ELECTRON MICROSCOPE. /AUTHOR/
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Supplemental Notes:
- No 32, pp 53-66
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Authors:
- Sierra, R
- Publication Date: 1968-6
Media Info
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Serial:
- Bull Liaison Labs Routiers /France/
- Publisher: Laboratoire Central des Ponts et Chausees (LCPC)
Subject/Index Terms
- TRT Terms: Bonds; Calcium; Calcium oxide; Cohesion; Concrete tests; Crystallography; Electron microscopes; Gels; Hydration; Morphology; Pastes; Portland cement; Silicates; Studies; Tobermorite
- Old TRIS Terms: Amorphous; Calcium silicate gel
- Subject Areas: Highways; Materials;
Filing Info
- Accession Number: 00213273
- Record Type: Publication
- Files: TRIS
- Created Date: Apr 28 1994 12:00AM