Title:
EVALUATION OF FLY ASH BASED CONCRETES CONTAINING POST-CONSUMER GLASS AGGREGATES
Author(s):
Colter Roskos, Michael Berry, and Jerry Stephens
Publication:
Symposium Paper
Volume:
314
Issue:
Appears on pages(s):
1-14
Keywords:
Concrete; Recycled materials; Fly ash; Glass; Sustainable
DOI:
10.14359/51689740
Date:
3/1/2017
Abstract:
Concrete is the world’s most used construction material, and although it offers many advantages over other building materials from an environmental perspective (e.g., durability, thermal properties), the negative environmental impact of traditional concrete is of growing concern as its use increases. This paper highlights significant findings from a recent study focused on identifying alternate materials to be used in concrete to mitigate its negative environmental impacts. This study specifically researched structural-grade concrete in which 100 percent of the portland cement was replaced with self-cementitous hydraulic fly ash and the aggregates were replaced with pulverized post-consumer glass from the container industry. In particular, this paper presents the results of mechanical (compressive and tensile strength, elastic modulus), and durability (ASR, absorption, abrasion, chloride permeability) tests performed on two such concretes made with fly ashes from power plants in Wyoming and Kansas. Overall, the fly ash/glass concretes tested in this research program showed promise for use in the construction industry. They exhibited 28-day unconfined compression strengths in excess of 4,000 psi (28 MPa); although their corresponding
tensile strengths were somewhat lower than would be expected based on the behavior of conventional concretes. Relative to durability, the results of the ASR tests were mixed, depending on the manner in which the ASR testing was conducted. The absorption results and abrasion resistance of the two concretes were found to be similar to conventional concretes, and the permeability test results indicate a total charge passed of less than 1,000 coulombs, which correlates with “very low” likelihood of chloride ion penetration being an issue.