Influence of Fibres on the Strain Hardening Behaviour of Ultra-High-Performance Geopolymer Concrete: A Review

Abstract

Continuous cement manufacturing has increased the percentage of CO 2 emitted into the air, thereby increasing the problem of global warming and its damaging effects on the environment. Therefore, adopting a more sustainable strategy to replace conventional concrete has become essential. Geopolymer concrete (GPC) is a relatively new engineering material that is sustainable and innovative and has several advantages over conventional cement concrete. The use of supplementary cementitious materials mixed with alkali-activated solutions can be substituted for cement in GPC manufacturing. Generally, "ultrahigh-performance concrete" (UHPC) is referred to as a composite material made from ordinary Portland cement (OPC) with better durability, compressive strength which is extremely high, and toughness. Recently, studies have been conducted to develop UHPC using geopolymer technology with a performance comparable to that of UHPC. However, comparable to UHPC, ultra-high-performance geopolymer concrete (UHPGPC) without fibres may show significant brittleness with the strength increase. The intrinsic brittle nature of concrete can lead to the cracking and eventual failure of concrete structures. Consequently, it becomes necessary to add fibres to increase the ductile performance of UHPGPCs. To enhance the practical uses of UHPGPCs and improvement in fundamental knowledge of material testing requirements and procedures, a detailed analysis of the strain-hardening properties of UHPGPCs is necessary. As a result, the impact of fibres on the strainhardening behaviour of GPCs and UHPGPCs is thoroughly reviewed in this work. The findings of this research will serve as an essential foundation for designing and developing UHP-GPC with better strain-hardening behaviour.