Progressive collapse of post-and-beam mass-timber buildings: Quantifying robustness and dynamic increase factors
Journal of Building Engineering, cilt.130, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 130
- Basım Tarihi: 2026
- Doi Numarası: 10.1016/j.jobe.2026.117116
- Dergi Adı: Journal of Building Engineering
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Compendex, INSPEC
- Orta Doğu Teknik Üniversitesi Adresli: Evet
Özet
The growing adoption of post-and-beam mass-timber buildings in mid- and high-rise applications necessitates a clearer understanding of their robustness against progressive collapse to support safe structural design. To address key knowledge gaps for this structural typology, a representative six-storey post-and-beam mass-timber building was investigated under 13 ground-level column-removal scenarios. The objectives were to (i) quantify its robustness and identify governing failure modes under sudden column loss using incremental dynamic analysis (IDA), (ii) determine dynamic increase factors (DIFs), and (iii) evaluate the suitability of pushdown-based pseudo-static analysis (PSA) for practical progressive-collapse assessment. A three-dimensional finite-element model was developed in Abaqus using a modelling procedure validated against scaled 2D and 3D experiments. The behaviour of all structural members and connections was parameterised using mean mechanical properties. Particular attention was given to modelling the floor system and connections to capture alternative load-bearing mechanisms following column loss, thereby providing a realistic representation of post-removal structural behaviour. Results show that the building withstood the accidental design load specified by Australian Standards under all single ground-level column-removal scenarios, retaining a minimum safety margin of 56%. For equivalent-static assessment of similar systems, DIF values of 1.85 for away-from-bracing column removals and 1.35 for removals adjacent to inverted-V bracing are recommended. PSA estimated DIF with reasonable accuracy for away-from-bracing removals while the response remained elastic; however, it generally overpredicted collapse capacity beyond the elastic domain and was inaccurate for bracing-adjacent removals.