EFFECT OF MELMENT ON THE HYDRATION OF WHITE PORTLAND CEMENT

The purpose of this paper is to investigate the effect of the superplasticizer melment on the hydration of cement. White portland cement was used. The blaine surface area was 4496 square cm per gramme. Known amounts of cement (with a water solid ratio (w/s) of 0.5) were put in polythene bags and hydrated in the presence or absence of melment (1 wt%) hydration was stopped at different times using isopropyl alcohol and ether and the samples were dried at 105 degrees c. Setting times were determined using a vicat needle. The water solid ratio was kept at 0.3. The non evaporable water content of the hydrated samples was determined by noting the weight loss at 1000 degrees c. Electrical conductivities of the hydrating pastes were determined using a systronic conductivity bridge. X ray diffraction patterns were taken with a x-ray diffractograph using cu k alpha radiation. Compressive strengths of the cement cubes was determined at different time intervals with w/s=0.3, and the amount of melment absorbed at the cement surfaces determined using a bausch and lomb spectronic-2000 spectrophotometer. These results show that melment retards the hydration of portland cement while increasing in compressive strength. The former is due to the absorption of melment over the cement surface, and the latter may be due to a decreasing number of large capillary pores. A hydration model is proposed.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/00088846
• Corporate Authors:

  Pergamon Press, Incorporated

  Maxwell House, Fairview Park
  Elmsford, NY  United States  10523
• Authors:
  • Singh, N B
  • Singh, A K
• Publication Date: 1989-7

Language

• English

Media Info

• Pagination: p. 547-553
• Serial:
  • Cement and Concrete Research
  • Volume: 19
  • Issue Number: 4
  • Publisher: Elsevier
  • ISSN: 0008-8846
  • Serial URL: http://www.sciencedirect.com/science/journal/00088846

Subject/Index Terms

• TRT Terms: Capillarity; Hydration; Pores (Geology); Portland cement; Size; Strength of materials; Superplasticizers
• Uncontrolled Terms: Increase; Pore
• ITRD Terms: 5901: Capillarity; 4758: Cement; 9014: Dimension; 7195: Hydration; 9032: Increase; 4725: Plasticizer; 5938: Porosity; 5544: Strength (mater)
• Subject Areas: Geotechnology; Materials;

Filing Info

• Accession Number: 00498604
• Record Type: Publication
• Source Agency: Transport and Road Research Laboratory (TRRL)
• Files: ITRD, TRIS
• Created Date: Sep 30 1990 12:00AM