Fresh Properties, Strength, and Durability of Fiber-Reinforced Geopolymer and Conventional Concrete: A Review

Abstract

Reducing the environmental footprint of the construction industry in general and concrete in particular is essential. The addition of synthetic and natural fibers to concrete mixes at appropriate dosages enhances durability and strength and extends the lifespan of concrete infrastructures. This study reviews the geometric and mechanical properties of selected fibers such as steel, basalt, polypropylene, polyvinyl alcohol, polyethylene, glass, carbon, and natural fibers and their impact on concrete fresh, mechanical, and durability properties when combined in different configurations. The study focuses on the effect of blending fibers with concrete mixes that use alkali-activated binders based on recycled industrial byproducts such as slag and fly ash and thereby contribute to reduction of CO2 contribution through complete or partial replacement of Ordinary Portland cement (OPC). As a result, the effect of binder content, binder composition, alkaline activator concentration, and water-to-binder (w/b) ratio on fresh properties, mechanical strength, and durability of concrete with blended fibers is also evaluated in this study. The properties of fiber-reinforced concrete with alkali-activated binder and conventional OPC binders are compared. Fiber-reinforced concrete with alkali-activated binders that are based on industrial byproducts may represent sustainable alternatives to conventional concrete and offers competitive fresh and mechanical properties when fiber properties, fiber content, w/b ratio, binder type, and dosage are carefully considered in concrete mix design.

Structure and Properties Improvement by Recipe Factors of Geopolymer Basalt Fiber Reinforced Concrete for Building Enclosing Structures

“…The optimal amount of fibers in the geopolymer matrix makes it possible to obtain a composite with higher compressive and flexural strength. However, an excessive amount of BF in this case, 2% or more, leads to poor compaction and increased porosity, which will reduce the strength properties [60]. The positive effect of basalt fiber at optimal dosages on the strength characteristics of geopolymer composites is also confirmed by a number of the following studies [57,58,64,65].…”

“…It can be concluded that changing the molarity of NaOH solution from 8 M to 14 M in the alkaline activator does not significantly affect the density of geopolymer mixtures, but does affect their workability, reducing cone settlement. This is due to the fact that higher concentrations of sodium hydroxide solution accelerate the setting process of fresh geopolymer concrete and increase its viscosity, while reducing workability parameters [60]. For example, in [61], self-compacting concrete mixtures with a higher content of sodium hydroxide (12 M) showed lower fluidity than mixtures where an activator with a lower content of sodium hydroxide (8 M) was used.…”

“…The most effective composition of the alkaline activator contains a NaOH solution with a molarity of 12 M. The higher the molarity of the NaOH solution, the greater its conservative activity. A high open capacity ensures the activation of a larger number of GGBS particles, which ultimately leads to a stronger and denser composite structure [60]. The aluminosilicate component used in this case in the form of GGBS with a certain granulometry has the best compatibility when included with an alkaline activator, where a NaOH solution with a molarity of 12 M is used.…”

Effect of Pulping Waste Liquid on the Physicochemical Properties and the Prediction Model of Wheat Straw Residue Granular Fuels

“…However, the traditional granular fuels made by molding technology has low quality, and various pollutants are released during the combustion process [ 3 , 4 ]. Consequently, selecting suitable additives is a crucial solution to improve the quality of granular fuels and reduce power consumption during granularizing processes [ 5 ].…”

Freeze–Thaw Damage Characteristics of Concrete Based on Compressive Mechanical Properties and Acoustic Parameters

“…Concrete is a widely selected construction material because of its higher compressive strength, excellent durability, and ease of use [ 1 , 2 , 3 , 4 ]. Nevertheless, concrete is also subject to freeze–thaw damage, which can significantly reduce its mechanical properties and lead to premature failure [ 5 ].…”