Interfacial performance of wood waste fibers in cementitious composites: Species-dependent mechanisms and alkali treatment effects
Construction and Building Materials, cilt.537, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 537
- Basım Tarihi: 2026
- Doi Numarası: 10.1016/j.conbuildmat.2026.147178
- Dergi Adı: Construction and Building Materials
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Compendex, INSPEC
- Anahtar Kelimeler: Alkali modification, Cement-based composites, Fiber–matrix interface, Mechanical properties, Species-dependent behavior, Wood fiber reinforcement
- Bursa Uludağ Üniversitesi Adresli: Evet
Özet
The sustainable use of construction and demolition wood waste in high-performance cementitious composites is constrained by limited understanding of species-dependent behavior and treatment–structure–property relationships. This study examines the combined effects of botanical origin (softwood vs. hardwood) and alkali treatment duration (12, 24, and 36 h in 1 M NaOH) on the microstructural, chemical, and mechanical performance of wood fiber–reinforced mortars. Both wood fiber types, obtained from industrial residues and standardized by passing through a 0.8 mm sieve, are incorporated into the mixtures at volume fractions of 0.5%, 1.0%, and 1.5%. Characterization included SEM, SEM–EDS, FTIR, compressive and flexural strength tests, and water absorption measurements. Results show that 12 h alkali treatment effectively removed hemicellulose and partially reduced lignin while preserving cellulose integrity, increasing surface roughness and fibrillation. Prolonged treatment (36 h) caused cellulose degradation and cell wall collapse, particularly in hardwood fibers due to thinner walls. Fiber incorporation reduced compressive strength in proportion to fiber content, mainly due to increased porosity and matrix discontinuity. However, flexural strength improved significantly in optimally treated mixtures, with 12h–treated hardwood fibers achieving up to 40% higher strength than the control. SEM–EDS revealed different interfacial mechanisms: softwood fibers primarily exhibited frictional load transfer, whereas hardwood fibers showed localized mineralization and micro-anchorage within vessel pits, enhancing crack-bridging efficiency. Overall, fiber origin and alkali exposure interact synergistically to control interfacial chemistry, microstructural stability, and mechanical performance. Short-duration alkali treatment of hardwood fibers is identified as the most effective strategy to maximize flexural performance while minimizing compressive strength loss.