High-Temperature Performance of Alkali-Activated Materials and Geopolymers: Mechanisms and Design Perspectives
ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING, cilt.52, ss.1-31, 2026 (SCI-Expanded)
- Yayın Türü: Makale / Derleme
- Cilt numarası: 52
- Basım Tarihi: 2026
- Doi Numarası: 10.1007/s13369-026-11757-2
- Dergi Adı: ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING
- Derginin Tarandığı İndeksler: Materials Science & Engineering Collection (ProQuest), Technology Collection (ProQuest), Science Citation Index Expanded (SCI-EXPANDED), zbMATH
- Sayfa Sayıları: ss.1-31
- Bilecik Şeyh Edebali Üniversitesi Adresli: Evet
Özet
Alkali-activated materials (AAMs) and geopolymers have attracted increasing attention as low-carbon alternatives to ordinary Portland cement, particularly for structures exposed to elevated temperatures. This review critically evaluates their high-temperature performance by integrating current knowledge on binder chemistry, gel evolution, microstructural transformations, and mechanical response. Calcium content is a key controlling parameter: low-calcium N–A–S–H systems generally show higher thermal stability, while high-calcium C–(A)–S–H systems offer greater early strength but degrade earlier; hybrid systems exhibit intermediate, composition-dependent behavior. Mechanical strength may be preserved or slightly enhanced at 200–400 °C through continued reaction and gel densification, while dehydration, phase transformations, and microcracking generally cause pronounced degradation above approximately 600 °C. At temperatures above 800 °C, crystallization and viscous sintering may partially stabilize the microstructure depending on system composition. Compared with OPC-based materials, AAMs typically exhibit lower mass loss, reduced spalling tendency, and higher residual strength, although performance remains sensitive to heating rate, cooling regime, and curing conditions. Overall, thermal behavior is governed by the coupled effects of gel chemistry, pore evolution, and phase stability. Future research should prioritize standardized thermal-testing protocols, realistic fire and cooling scenarios, long-term post-fire durability, quantitative microstructure–property models, low-carbon activators, and structural-scale validation to support performance-based design.