Title: Utilization of Fly Ash in the Development of a Cost-Effective Cementitious Product

Author(s): S. L. Sarkar, A. Kumar, D. K. Das, and G. Banerjee

Publication: Symposium Paper

Volume: 153

Issue:

Appears on pages(s): 439-458

Keywords: binders (materials); C-S-H; ettringite; fly ash; hydration; lime; strength; wastes; Materials Research

DOI: 10.14359/1082

Date: 6/1/1995

Abstract:
The individual binding capacity of fly ash in lime bearing systems and gypsum on its own is well established. This study was aimed at utilizing gypsum as phosphogypsum and industrial lime in conjunction with high volume fly ash to develop a cost-effective cementitious binder product by advantageously utilizing the individual binding capacity of the materials. The materials were first fully characterized chemically and mineralogically to evaluate their potential as building material components. Different mixture proportions were tested. Compressive strength data of different mixtures at one day, 3, 7, 14, 21, and 28 days are presented. These are correlated with the hydration properties at corresponding ages studied by means of XRD, SEM/EDXA, and DTA. The discussion relates to the roles of the individual components in the development of strength properties. Products with an interlocking microstructure and compressive strengths of over 12 MPa after 28 days of hydration are described. The cost effectiveness and possible applications of cementitious products that can be developed with such a system are also described.