Mechanical Characterization of Self-Compacting Geopolymer Concrete using AR Glass Fibers

Abstract

This paper researches the mechanical property of self-compacting concrete-geopolymer concrete (SCGPC) that is the result of complete substitution of cement by industrial by-products, including fly ash, ground granulated blast furnace slag (GGBS), and silica fume. A mixture of fly ash (50%), GGBS (40%), and silica fume (10%) (M5 mix) is determined as the optimum binder mix that demonstrates the best compressive, tensile, and flexural strength when compared to other non-fiber mixes. The addition of alkali-resistant (AR) glass fibers also enhances mechanical properties, and the optimum strength values for a 1.5% fiber addition (M9 mix) are the highest. All mixes meet EFNARC (2002) requirements of workability and self-compaction. Beam testing reveals that fiber-reinforced beams exhibit increased load-bearing capacity, ductility, reduced crack propagation, and a fine crack distribution, with supplementary strength provided by shear reinforcement. The findings validate that AR glass fiber-reinforced SCGPC is a viable and ecological substitute to the traditional cement concrete system because it favors the utilization of industrial by-products, and it removes cement.

Introduction

The study focuses on creating a sustainable, high-performance concrete by fully replacing traditional cement with pozzolanic materials—fly ash, GGBS, and silica fume—while enhancing mechanical properties with alkali-resistant (AR) glass fibers. This approach reduces CO? emissions, improves durability, minimizes thermal cracks, and provides cost-effective construction. Superplasticizers are used to improve workability and enable self-compacting mixes.

Literature review highlights that adding glass fibers and pozzolanic materials can significantly enhance compressive, tensile, and flexural strength, though excessive fiber content can reduce workability or strength. Geopolymer concretes also demonstrate good chemical resistance and durability compared to conventional concrete.

Objectives include producing self-compacting geopolymer concrete (SCGPC), optimizing binder ratios, evaluating mechanical properties with varying AR glass fiber contents (0.5–2%), and assessing structural performance, crack control, and ductility in beams.

Materials used include fly ash, GGBS, silica fume, sodium silicate and hydroxide as alkaline activators, superplasticizers, and AR glass fibers. Ten mix designs (M1–M10) were tested, with specific proportions of these materials.

Experimental procedure involved machine mixing, casting cubes, cylinders, and beams, and curing at ambient conditions. Fresh properties were evaluated using EFNARC (2002) guidelines, and mechanical performance was measured at 7, 28, and 90 days.

Conclusion

1) The optimum binder mix is 50% Fly Ash, 40% GGBS, and 10% Silica Fume (M5 mix) that demonstrates high strength compared to non-fiber mixes. 2) Strength is improved by the addition of AR glass fiber, where 1.5% fiber (M9 mix) provides optimum compressive, tensile, and flexural strength. 3) Every mix conforms to EFNARC (2002) workability and self-compaction requirements. 4) Beam tests reveal that fiber-reinforced beams are stronger in load-bearing, enhanced ductility, and slow crack propagation. 5) Providing shear reinforcement gives more strength and resistance to cracks. 6) The paper affirms the fact that AR glass fiber-reinforced geopolymer concrete is a sustainable and eco-friendly substitute to cement concrete through the use of industrial by-products.

References

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Copyright

Copyright © 2025 Badavathu Rajgopal , Dr. I. V. Ramana Reddy. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.