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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Chemical reactions in the setting of cement ...

Lasseter, Franklin Powell, January 1900 (has links)
Thesis (PH. D.)--Columbia University, 1931. / Vita. "Reprint from ... articles in the Cement mill edition of Concrete, volume 38, numbers 3, 4 and 5, March, April and May, 1931." eContent provider-neutral record in process. Description based on print version record. "Bibliography of references cited": p. 45.
22

The effect of clays on the properties of masonry cement

Smothers, W. J. January 1940 (has links) (PDF)
Thesis (B.S.)--University of Missouri, School of Mines and Metallurgy, 1940. / The entire thesis text is included in file. Typescript. Illustrated by author. Title from title screen of thesis/dissertation PDF file (viewed April 6, 2010) Includes bibliographical references (p. 23) and index (p. 24).
23

The Effect of alkali upon Portland cement ... /

Steik, Karl Theodor. January 1900 (has links)
Thesis (Ph. D.)--University of Chicago, 1919. / "Private edition, distributed by the University of Chicago Libraries, Chicago, Illinois." Reprinted from University of Wyoming agricultural experiment station. Bulletin no. 122, December 1919, which has title: The effect of alkali upon Portland cement--II. "A Progress report on this problem was made in Bulletin 113 of the Wyoming station. Much of the work outlined on the following pages appeared in the earlier publication, but is included at this time to ... complete the final report." Also available on the Internet.
24

Development of high performance structural lightweight Portland cement concrete a thesis presented to the faculty of the Graduate School, Tennessee Technological University /

Thomason, James Charles, January 2009 (has links)
Thesis (M.S.)--Tennessee Technological University, 2009. / Title from title page screen (viewed on June 25, 2010). Bibliography: leaves 89-94.
25

X-ray diffraction study of high temperature reaction products in the barium oxide-silica-alumina-ferric oxide system

Schmidt, Heinrich. January 2001 (has links)
Thesis (Ph.D.)--University of Pretoria, 2001. / Summaries in Afrikaans and English. Includes bibliographies. Available on the Internet via the World Wide Web.
26

Determination of free lime in sai chuun cement

LEUNG, Wing Kai 01 June 1937 (has links)
No description available.
27

The effect of addition agents in grinding Portland cement clinker

Hill, Eugene Farrell, January 1940 (has links) (PDF)
Thesis (M.S.)--University of Missouri, School of Mines and Metallurgy, 1940. / The entire thesis text is included in file. Typescript. Illustrated by author. Title from title screen of thesis/dissertation PDF file (viewed March 9, 2010) Includes bibliographical references (p. 60-62) and index (p. 63-64).
28

Alternative solid fuels for the production of Portland cement

Akkapeddi, Srikanth, Schindler, Anton K. January 2008 (has links)
Thesis--Auburn University, 2008. / Abstract. Vita. Includes bibliographic references (p.269-278).
29

Hawaiian trachyte rock as a pozzolanic admixture in Portland cement concrete

Murakami, Hideo. January 1953 (has links)
Call number: LD2668 .T4 1953 M85 / Master of Science
30

The effect of gypsum phase components on the rheokinetics of cement paste

Migabo, Willy Mbasha January 2018 (has links)
Thesis (Doctor of Engineering in Civil Engineering)--Cape Peninsula University of Technology, 2018. / Rheological properties of most ordinary Portland cements are dictated by the hydration reactions that their different phases experience. Cement clinker has four main phases with aluminate being the most reactive. Once in contact with water, the aluminate phase reacts rapidly and generally impedes the early hydration of other cement compounds such as calcium silicates that are responsible for the strength of cement systems. Consequently, the obtained matrix is stiff without much strength. Alternatively, calcium sulphate bearing materials are added within the clinker as set regulators of the aluminate phase hydration. For this purpose, natural gypsum is moslty gound with cement clinker as a source of sufficient sulphate, thereby keeping the cement paste plastic for a certain amount of time, allowing the hydration of silicate phases that are responsible for the early and later strength. However, the heat generated within the mill during the grinding process of clinker and gypsum causes a partial dehydration of natural gypsum into hemihydrate. The final ground cement product is thus comprised of two unexpected types of calcium sulphate bearing materials in an unpredictable proportion. Due to the difference in their solubility, the hydration of the aluminate phase can variably be altered which consequently affects the rheokinetics of the cement paste. Currently, the effect of the available amount of hemihydrate and natural gypsum in the cement sulphate phase, on both the hydration and rheology of ordinary Portland cements (OPC), are not well-understood. An ordinary Portland cement clinker was sampled during the production process of CEM I under stable kiln operations at a local cement plant. This was ground without any form of calcium sulphate bearing material and the final product was considered as relatively pure cement clinker. The degree of natural gypsum degeneration was achieved by partially replacing fractions of hemihydrate with those of natural gypsum. Firstly, the individual effect of these calcium sulphate bearing materials on the hydration kinetics was studied by varying their concentrations from 2-7% within the cement system. Secondly, the effect of their mix proportions at an optimum calcium sulphate concentration on cement paste rheokinetics was investigated. This research confirmed the findings of previous investigations relative to the effect of calcium sulphate on the hydration kinetic , giving new insight on the rheokinetics of cement paste with mix proportions of various calcium bearing materials. Results showed that the reaction rates of cement systems with hemihydrate were faster than those with natural gypsum and generally tended to decrease with the increase in their concentrations. Cements with hemihydrate experiencing shorter dormant durations than those with natural gypsum, likely due to the fact that the consumption rate of calcium sulphate was higher in cement systems with hemihydrate than those with natural gypsum. Consequently, before the exhaustion of sulphate ions, cement systems with hemihydrate had higher degrees of hydration and became almost similar thereafter. More ettringite and portlandite were formed in cement systems with hemihydrate as compared to those with natural gypsum. The amount of ettringite increased with the increase in calcium sulphate concentration up to 4% and thereafter remained constant. Conversely, the amount of portlandite decreased with the increase in calcium sulphate and also remained unchanged after 4%. The strength development of the cement microstructure depended on the concentration of hemihydrate within the suspension. The rigidification of the newly formed network was affected at higher hemihydrate fractions. Rheological parameters were more pronounced when the concentration of hemihydrate exceeded 50%. Below this hemihydrate concentration, cements had almost similar flow properties as those with only natural gypsum. Large changes in yield stress values and variation in plastic viscosity values of approximately 50% were observed. The trend of mixes dynamic yield stress were similar to their corresponding strength rate developments. This rheological behaviour was primarily attributed to the morphology change of ettringite that was triggered by the presence of a higher hemihydrate concentration. It was also noticed that physical performances of cement systems depended on their respective microstructure developments.

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