Investigating the Response of Bolted Wood Connections Subjected to Bast Loads
Notice bibliographique
Résumé
With recent improvement in wood manufacturing technologies, taller and larger wooden structures are being constructed, thereby increasing the risk for potential damage due to a blast threat against such structures. Recent studies on the effects of high strain rate in wood have been undertaken, however the vast majority of these studies have focussed on structural elements with idealized boundary conditions. Some studies included realistic connections as the boundary conditions, but little progress has been made to date in order to quantify the behaviour of connections in isolation. The current study aims to investigate the response of steel-wood-steel bolted connections when subjected to blast loads. This includes determining the dynamic increase in resistance and stiffness for stocky and slender bolts in both the parallel and perpendicular to grain directions. The study also explores analytical solutions to predict the joint behaviour and discusses the validity of current blast design provisions. Bolted wood connections were investigated under both static and simulated blast loading using the University of Ottawa’s shock tube. The study found a dynamic increase in resistance and stiffness when the failure mode was dominated by wood crushing in both the parallel and perpendicular to grain directions. No increase in resistance or stiffness was observed when bolt yielding dominated the failure. A loss of ductility was observed under dynamic loading for the parallel to the grain connections designed to fail in wood crushing. It was found that the use of self-tapping screw reinforcement was an effective method of preventing premature splitting failures and enhancing the performance of a connection. The results showed that connections which engaged the fastener in bending exhibited more favourable behaviour than connections which engaged only in wood crushing. A two degree-of-freedom model was capable of modelling the connections even when the support frame system had some flexibility. The validated model was used to investigate cases where the connection could contribute to the energy dissipation. It was found that the performance of the assembly improved when the connections were considered. Recommended future work includes an investigation of brittle failure modes in bolted connections, exploring connections with more deformation capacities, and expanding the experimental component of the study to include full-scale structural assemblies with wood elements and boundary connections. Limited design recommendations have been proposed in the current study, however testing at the assembly level could shed more light on such an important topic.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,001 |
| Méta-épidémiologie (sens strict) | 0,001 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,001 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,001 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,001 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,003 | 0,001 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule source (Gemma direct ou Codex distillé), pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».