Work

A Review on the Fracture Toughness and Long‐Term Durability of Fly Ash–Based Cementitious Composites

Year: 2026

Type: article

Abstract: Fly ash is widely used as a supplementary cementitious material to reduce Portland cement consumption and enhance the long‐term performance of cementitious composites. However, meaningful comparison of fracture toughness and durability reported across published studies remains challenging because of differences in specimen geometry, testing methods, curing conditions, and reporting practices. This review critically evaluates recent advances in the fracture toughness and long‐term durability of fly ash–based cementitious composites through a structured synthesis of peer‐reviewed studies published between 2020 and 2025. A normalization‐based benchmarking framework was adopted to compare fracture and durability performance relative to corresponding control mixtures, thereby improving cross‐study comparability. The review examines key fracture parameters, including critical stress intensity factor and fracture energy, together with durability indicators such as chloride permeability, sulfate resistance, freeze–thaw resistance, and carbonation depth. The synthesized evidence indicates that moderate fly ash replacement levels of approximately 25%–35% consistently provide the most balanced improvements in fracture resistance and durability through pore refinement, interfacial transition zone densification, and enhanced crack path tortuosity. In contrast, replacement levels exceeding approximately 40% may increase carbonation susceptibility under inadequate curing despite continued improvements in transport resistance. This review further integrates fracture mechanics, durability behavior, and microstructural evolution within a unified interpretation framework and identifies current research gaps, including the need for standardized fracture testing protocols and long‐term field validation. The proposed benchmarking approach provides practical guidance for sustainable mix design and supports the development of more durable and resilient cementitious composites.

Source: Advances in Materials Science and Engineering

DOI: 10.1155/amse/5460433

Authors: Nancy Mweni Paul, Genson Murithi, Jackson Wachira Muthengia

Institution: University of Embu

Language: English

Topic: Concrete and Cement Materials Research

Subfield: Civil and Structural Engineering

Field: Engineering

Domain: Physical Sciences

SDG: Responsible consumption and production

Open Access status: gold

Estimated APC paid: $2,670