Abstract A novel method is developed for reusing the waste glass fiber-reinforced polymer (GFRP) powder as a precursor in geopolymer production. Several activation parameters that affect the workability and strength gain of GFRP powder-based geopolymers are investigated. The results of an experimental study reveal that the early strength of GFRP powder-based geopolymer pastes develops slowly at ambient temperature. The highest compressive strength of GFRP powder-based geopolymer pastes is 7.13 MPa at an age of 28 days. The ratio of compressive strength to flexural strength of GFRP powder-based-geopolymers is lower than that of fly ash and ground granulated blast furnace slag (GGBS)-based geopolymers, indicating that the incorporation of GFRP powder can improve the geopolymer brittleness. GGBS is incorporated into geopolymer blends to accelerate the early activity of GFRP powder. The binary geopolymer pastes exhibit shorter setting times and higher mechanical strength values than those of single GFRP powder geopolymer pastes. The GGBS geopolymer concrete mixture with 30 wt% GFRP powder displayed the highest compressive strength and flexural strength values and was less brittle. The developed binary GFRP powder/GGBS-based geopolymers reduce the disadvantages of single GFRP powder or GGBS geopolymers, and thus, offer high potential as a building construction material.
Evaluation of Alternative Sources of Supplementary Cementitious Materials for Concrete Materials
This study characterized and evaluated the use of reclaimed fly ash (RFA) and reclaimed ground bottom ash (GBA) as alternative sources of supplementary cementitious materials (SCMs) for the production of concrete mixtures. Conventional Class F fly ash (FA) was also evaluated for comparison. The effects of SCM content on fresh and hardened properties of concrete were investigated by replacing 10%, 20%, and 30% of cement by mass. Characterization results showed that all three ashes met ASTM C618 chemical requirements (i.e., sum of SiO 2 + Al 2 O 3 + Fe 2 O 3 , CaO, SO 3 , moisture content, and loss of ignition) and 7- and 28-days strength activity index (SAI) requirements for Class F FA. In addition, RFA exhibited slightly higher SAI at 28 days of curing, followed by GBA and FA. In relation to fresh concrete properties, FA increased the concrete slump compared with the control mixture, whereas RFA and GBA decreased the concrete slump. However, GBA produced more significant slump decrements than RFA, which was attributed to the irregular angular particles of GBA. Generally, all the coal ashes produced decrements in air content compared with the control mixture. Comparatively, among the three ashes, GBA exhibited the highest 28- more »
- Award ID(s):
- 1852535
- Publication Date:
- NSF-PAR ID:
- 10321207
- Journal Name:
- Transportation Research Record: Journal of the Transportation Research Board
- ISSN:
- 0361-1981
- Sponsoring Org:
- National Science Foundation
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