Notice bibliographique
Résumé
Advanced Cementitious Materials (ACM’s) are products with materials found in conventional concrete (cement, silica fume, sand, superplasticizer, and water) plus distinctive materials like fibers (steel, carbon) and quartz. The superiority of ACM’s in terms of strength, ductility, and durability marks it as high potential replacement of traditional concrete. The growing expansion of ACM applications and technical experience gained in the last two decades in counties including Japan, Germany, Austria, Australia, USA, Denmark, Canada, France, and the Netherlands results in new frontier of cement materials used in infrastructure. The economic feasibility of ACM’s has been demonstrated in footbridges, outstanding bridges, and large pre-cast series. Furthermore safety and durability of ACM’s, especially of Ultra-high performance concrete (UHPC) has been proven encouraging further research efforts. This research is one part of an ongoing research under the supervision of Professor D.A. Hordijk at the Technical University of Delft on the application of ACM’s in infrastructure. The biggest potential for new infrastructure with ACM’s is in precast girders and thin plates. Throughout utilizing the excellent properties of ACM’s like UHPC, a new lighter- weight, durable, efficient, and adaptable superstructure has been developed in this study to replace the existing traditional design of bridges in the nearby future. One example of the approach taken in this thesis is the benefit of long life-cycle. Due to dense matrix, which prevents the ingress of detrimental substances apply UHPC selectively in the superstructure where it required to sustain high level of durability. Another example of the mindset of this thesis is lightweight design, means material distribution follows the forces distribution. In this thesis the outcome of an extensive material study was an overview of the ACM’s properties, time depended behavior, non-linear behavior, design standards, and field of application. Based on the material study different parameters are analyzed to enhance the understanding of the behavior of structure with ACM. It has been found that structural elements from UHPC are far more efficient then their corresponded traditional concrete structures. The maximum crack size is significantly lower, the slenderness is much higher which result in higher efficiency and reduction of the dead loads. Also the shrinkage and creep of ACM’s is studied. The time-depended imposed deformation of UHPC elements (plate, flange, truss member) with different sizes cause stresses in the model ends up as transverse cracks when the deformation is restrained. Based on the drawn conclusion of the parametric study, the design stage of the new ACM superstructure was initiated complying with requirements & boundaries according to the NEN norms and SETRA (French recommendation for UHPC). The new superstructure is 35% lighter than traditional solution, with efficient material distribution, built only from concrete, with elegant simple solutions. The low reliability of the fibers as replacement for reinforcement well-thought-out in the design. Some suggestion for future research in the field of modular adaptable superstructure have promising potential as far as applying ACM’s.
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 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,001 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,002 | 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 ».