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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.
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Simultaneous use of bismuth trioxide and mill scale for ternary blended geopolymer composite in radiation shielding applications
The present study evaluates Mill scale which is a steel industry waste and bismuth trioxide simultaneously as a potential radiation shielding material in geopolymer composite. An innovative and first of its kind lead-free design has been developed for making radiation shielding materials using mill scale and bismuth trioxide as shielding aggregates and industrial wastes such as fly ash and blast furnace slag as precursors for the geopolymer composite. The mill scale and bismuth trioxide based composite material are characterized for their radiation shielding characteristics based on shielding parameters commonly used in radiation shielding like linear attenuation coefficient (μ), half value thickness (HVT) and Mean Free Path (MVP) for 0.662 MeV energy. The determined shielding parameters are compared with traditional shielding materials like concrete with heavy aggregates. X-Ray diffraction studies have confirmed the presence of Bismuth ferrite as the major shielding phase responsible for radiation shielding. The mechanical properties of the prepared composites are determined for their strength in direct compression. Depending upon the radiation shielding parameters like linear attenuation coefficient and half value thickness an optimum dosage of mill scale and bismuth trioxide as a shielding composite to provide adequate shielding for X-Ray diagnostic and medical facilities against X-ray photons of low intensity has been recommended. The highest linear attenuation coefficient values of fly ash and slag based geopolymer composites had been observed to be 0.208 and 0.225, respectively.
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- Award ID(s):
- 1818697
- PAR ID:
- 10567830
- Publisher / Repository:
- ScienceDirect: ELSEVIER
- Date Published:
- Journal Name:
- Progress in Nuclear Energy
- Volume:
- 172
- Issue:
- C
- ISSN:
- 0149-1970
- Page Range / eLocation ID:
- 105213
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1016/j.pnucene.2024.105213
