Seismic analysis of telecommunication towers mounted on building rooftops
Notice bibliographique
Résumé
This thesis deals with the assessment of seismic accelerations in buildings and the seismic analysis of components installed on building rooftops, with special focus on operational telecommunition towers during and after earthquake shaking. First, acceleration data recorded during the 1999 Chi Chi earthquake from 11 instrumented buildings located in Taiwan were studied. Fundamental building periods were extracted by system identification and compared to those evaluated according to the equations proposed in the 2005 edition of the National Building Code of Canada (NBCC). Next, rooftop acceleration spectra and time histories were evaluated using 3-D finite element building models; three models of instrumented buildings were calibrated using accelerograms from the Chi Chi earthquake and the fourth model is a building located in downtown Montreal. The building models were subjected to 44 historical strong motion accelerograms and 30 synthetic accelerograms compatible with the target uniform hazard spectra specified in NBCC 2005 for Montreal. Based on both the experimental and numerical results, a maximum rooftop acceleration amplification of 4 is proposed for low/medium rise buildings and 3 for flexible high-rise buildings (T > 1.7 s). In the second stage, a simplified method for the prediction of seismic shear forces and overturning moments at the base of self-supporting steel lattice telecommunication towers mounted on building rooftops is presented. The proposed method involves the estimation of four parameters: the rooftop seismic acceleration, the mass distribution profile of the tower along its height, the maximum acceleration amplification at the tower top, and the fundamental sway mode shape of the tower on a rigid base. The method was validated by means of numerical results of nine generated building-tower combinations composed of three towers assumed to be mounted on three of the building models studied in the first stage of the research. The building-tower combinations were subjected to the same sets of earthquake records used for the prediction of accelerations. It was found the proposed method yields conservative results in all the cases analyzed. In addition, the empirical component force amplification factor for telecommunication towers as proposed in the NBCC 2005 was compared to the factors evaluated for the towers of the 16 building-tower combinations. Improved component force amplification factors based on rational analysis are proposed.
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 distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,001 | 0,000 |
| Bibliométrie | 0,001 | 0,002 |
| 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) | 0,000 | 0,000 |
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 tête enseignante, 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 ».