Article 2025 · 2 atıf

Mechanical, microstructural, and environmental performance of alkali-activated slag mortar with metakaolin and glass fiber

Sallai, Hind Hidayet, Benli, Ahmet, Oz, Ali, Genc, Gokhan, Bouhamou, Nasr Eddine, Toklu, Kenan, Kaplan, Gokhan, Aydin, Abdulkadir Cuneyt

Özet

This study investigates the combined effects of metakaolin (MK) and glass fiber (GF) incorporation on the mechanical, microstructural, and environmental performance of alkali-activated composites (AACs) formulated from granulated blast furnace slag (GBFS). Nine different AAC mixtures were prepared by varying MK (0 %, 10 %, and 20 %) and GF (0 %, 0.5 %, 1 %) contents. Mechanical strength, elastic modulus, sorptivity, thermal resistance, and toughness were evaluated following heat curing at 80 degrees C for 24 h. Mercury intrusion porosimetry (MIP) analysis revealed that the addition of MK significantly reduced total pore volume and refined the pore structure, thereby enhancing density and mechanical integrity. The optimal composition (MK10GF0.5) exhibited the highest compressive strength (44.56 MPa), flexural strength (5.92 MPa), and elastic modulus (32.87 GPa), along with reduced water absorption and sorptivity. Scanning electron microscopy (SEM) and EDS analyses confirmed the formation of a dense, homogeneous matrix with strong fiber-matrix interfacial bonding. Hightemperature exposure tests (250-750 degrees C) demonstrated that MK and GF incorporation significantly improved thermal stability, reducing weight loss and retaining higher residual strengths compared to the reference mixture. Life cycle assessment (LCA) results indicated that while GF and MK improve mechanical performance, they also increase environmental impacts relative to the control mixture; however, the overall use of recycled slag contributed positively to the sustainability profile. By linking pore refinement and mechanical enhancement with sustainability evaluation, this research provides new insights into the design of eco-efficient AACs. The findings underscore the practical significance of optimized MK-GF dosages in developing durable, thermally stable, and environmentally responsible alternatives to Portland cement-based materials, thereby supporting the transition toward sustainable construction practices.

Anahtar Kelimeler

Alkali-activated composites Metakaolin Glass fiber reinforcement Mercury intrusion porosimetry (MIP) Life cycle assessment (LCA) Microstructural characterization DURABILITY

WoS Kategorileri

Construction & Building Technology Engineering, Civil Materials Science, Multidisciplinary

Künye

Dergi: CONSTRUCTION AND BUILDING MATERIALS
Yıl: 2025
Cilt: 501
ISSN: 0950-0618
eISSN: 1879-0526
DOI: 10.1016/j.conbuildmat.2025.144285
WoS UID: WOS:001723506700001

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