1. ERDC Knowledge Core
2. Pre - Engineer Research and Development Center (ERDC)
3. Concrete Laboratory - (8/1/1972 - 4/16/1978)
4. Publication
5. Miscellaneous Paper

Title:	Examination of cement pastes, hydrated phases, and synthetic products by X-ray diffraction
Authors:	United States. Army. Office of the Chief of Engineers. Mather, Katharine.
Keywords:	Cement pastes Hydrates Portland-cements Synthetic products X-ray diffraction
Publisher:	Concrete Laboratory (U.S.) Engineer Research and Development Center (U.S.)
Series/Report no.:	Miscellaneous paper (U.S. Army Engineer Waterways Experiment Station) ; C-72-5.
Description:	Miscellaneous paper Abstract: Pastes or three cements were examined by X-ray diffraction at five ages in seven laboratories. Six of the laboratories used X-ray diffractometers and one used a focusing camera of the Guinier type. Six laboratories examined hydrated phases and synthesized hydrates. This is the first cooperative program in X-ray diffraction of portland cement pastes and synthetic hydrates of which we have knowledge. Pastes of all three cements were mixed at water-cement ratios of 0.35 and 0.65 and were examined after hydration had been stopped at ages of 1, 7, 28, 90, and 365 days. Pastes of a Type I cement at 0.35 water-cement ratio contained ettringite, tetracalcium aluminate monosulfate-12-hydrate, calcium hydroxide, calcium silicate hydrate gel, and residual cement constituents. Tetracalcium aluminate monosulfate-12-hydrate was detected at 7 plays and increased thereafter at the expense of ettringite. Compositions of pastes of this cement at 0.65 water-cement ratio were similar to those of water-cement ratio; the sequences of hydrates appearing and increasing, and cement constituents; diminishing and in some instances disappearing, were more conspicUOU3. The sequence of development and constituents present in pastes of a white cement at the two water-cement ratios resembled the Type I pastes. Pastes of a third cement containing no tricalcium aluminate formed less ettringite than pastes of the other two cements; ettringite persisted to one year; tetracalcium aluminate monosulfate-12-hydrate was detected only in trace amlounts. Spacings present in hydrated alite, hydrated j3-C 2S, tetracalcium aluminate hemicarbonate-12-hydrate, tetracalcium aluminate carbonate-11-hydrate, tetracalcium aluminate monosulfate-12-hydrate, unstable tetracaliurn aluminate-10. 5-hydrate, and ettringite, are reported.
Rights:	Approved for public release; distribution is unlimited.
URI:	http://hdl.handle.net/11681/11429
Appears in Collections:	Miscellaneous Paper