Effect of Phosphate-Based Compound on the Hydration of Cement and Cement components

ABOUT THE INTERNATIONAL CONCRETE ABSTRACTS PORTAL

  • The International Concrete Abstracts Portal is an ACI led collaboration with leading technical organizations from within the international concrete industry and offers the most comprehensive collection of published concrete abstracts.

International Concrete Abstracts Portal

  


Title: Effect of Phosphate-Based Compound on the Hydration of Cement and Cement components

Author(s): V. S. Ramachandran and M. S. Lowry

Publication: Special Publication

Volume: 148

Issue:

Appears on pages(s): 131-152

Keywords: admixtures; calcium aluminates; calcium silicates; calorimeters; cements; gypsum; hydration; portland cements; Materials Research

Date: 9/1/1994

Abstract:
The influence of a phosphonate-based admixture called aminotri (methylene phosphonic acid) (ATMP) on the hydration of C 3A, C 3A and 25 percent gypsum, and C 3S and Type I cements (normal, high-alkali, and low-alkali) was evaluated. Isothermal conduction calorimetric investigations of various mixes containing 0.03 to 0.05 percent of phosphonic acid, at water-cement ratios of 0.35 and 1.0, were carried out up to 72 hr. The ATMP acted as a super-retarder for all mixes studied. At a dosage of only 0.05, the exothermal effect for one of the high-alkali Type I cements was delayed by about 16 hr. The hydration of C 3A and C 3S was also retarded by about 40 to 45 min and more than 50 hr, respectively, at a dosage of 0.05 percent. In the C 3A and gypsum system, the third peak corresponding to the reaction of C 3A with ettringite was extended by about 8 to 9 hr.