Design of a steel footbridge over the river Esino
Auteur(s): |
Andrea Dall'Asta
Laura Ragni |
---|---|
Médium: | papier de conférence |
Langue(s): | anglais |
Conférence: | Footbridge 2005 (Second International Congress), Venezia, 06-08 December 2005 |
Publié dans: | Footbridge 2005 |
Année: | 2005 |
Abstrait: | The paper describes a footbridge to be constructed over the Esino river, near the mouth. The steel deck will consist of a three-span continuous beam with lengths of 31m-73m-31m, and the middle span will be supported by means of a cable system running under the girder. More specifically, the paper deals with the analysis at collapse of structures prestressed with external cables which are free to slip at the saddle points. Regarding the serviceability state the problem of estimating the dynamics effects due to pedestrian traffic is analyzed, considering the case of a small group of people walking and the case of a crowd crossing the bridge. The load conditions producing the highest accelerations on the footbridge are investigated, in order to compare them with the limits proposed by the technical codes and specific literature. Since these limits are exceeded, a double vibration control system was adopted so that the global energy dissipation capacity of the bridge is increased and the peaks of the response at the most critical frequencies are reduced. |
Mots-clé: |
passerelle
|