Role of Ground Glass Fiber as a Pozzolan in Portland Cement Concrete

Abstract

Millions of tons of fiberglass are produced annually for a variety of applications. Because of stringent quality requirements and operational characteristics of the manufacturing plants, a significant quantity of fiberglass that does not meet required specifications of the industry ends up as waste in landfills. This study investigated the use of ground glass fiber (GGF) that had been discarded by plants because it did not meet prescribed standards, as a supplementary cementitious material (SCM) for portland cement. Three replacement levels (10%, 20%, and 30% by mass) for portland cement in paste, mortar, and concrete mixtures were studied. Mechanical and durability properties of the mixtures were compared with two control mixtures: a mixture made up of 100% portland cement and a mixture with 25% Class F fly ash as a cement replacement material. It was observed in these studies that even though replacement of portland cement with GGF did not lead to any significant changes in the mechanical behavior of hardened concrete, there were significant improvements in durability properties at replacement levels up to as high as 20%. The use of GGF was found to improve significantly the resistance of mortar mixtures to alkali–silica reaction and sulfate attack. In addition, the use of GGF as an SCM significantly reduced the chloride ion permeability of concrete. Results of this study show that using GGF as an SCM can result in a better durability performance compared with a mixture with a similar level of Class F fly ash.

Evaluation of Selected Durability Properties of Portland Cement Concretes Containing Ground Glass Fiber as a Pozzolan

“…Furthermore, to study the microstructure of specimens as well as the mechanisms involved, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and X-ray diffraction analysis (XRD) were performed. Whereas earlier studies have shown the good mechanical properties of GGF-containing specimens ( 11, 12 ), the results of this study could be beneficial in evaluating the long-term durability properties of GGF-containing concrete and mortar specimens.…”

“…It was observed that replacing cement with GGF to 30% (mass-based) did not affect the mechanical properties of specimens. However, there was a significant improvement in short-term durability properties such as resistance against ASR (11,12), sulfate attack, and chloride ion penetration (12). This paper presents findings from selected durability studies that were conducted on GGF-containing (10, 20, and 30% of the cement mass) concrete and mortar specimens for two years.…”

“…In addition, use of this material improved durability properties of concrete such as resistance against ASR, sulfate attack, and chloride ion penetration. In recent studies, Rangaraju et al and Rashidian-Dezfouli and Rangaraju investigated the utilization of GGF as an SCM in concrete and mortar mixtures ( 11, 12 ). It was observed that replacing cement with GGF to 30% (mass-based) did not affect the mechanical properties of specimens.…”

“…It was observed that replacing cement with GGF to 30% (mass-based) did not affect the mechanical properties of specimens. However, there was a significant improvement in short-term durability properties such as resistance against ASR ( 11, 12 ), sulfate attack, and chloride ion penetration ( 12 ).…”

A Systematic Review of the Concrete Durability Incorporating Recycled Glass

“…In turn, reaction with calcium aluminates forms calcium sulfoaluminate indicated as ettringite, which causes internal pressure leading to concrete cracks. Formation of ettringite is an expansive process and can lead to cracking and a resultant loss of strength in the samples [62]. The following equation clarifies the mechanism of ettringite formation.…”