Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Flutter Vulnerability Assessment of Flexible Bridges
This work focuses on the vulnerability assessment of flexible bridges with respect to the aeroelastic instability known as flutter and two main contributions can be remarked. First, the Performance-Based Design approach is applied to the collapse limit state due to flutter. For the first time flutter derivatives are considered as random variables and the flutter problem is approached in a probabilistic way via Monte-Carlo simulations. A single-box girder deck is experimentally studied in the CRIACIV wind tunnel in order to make available data for this particular analysis. Interesting results are obtained both for this section model and for two rectangular cylinders. The second main contribution of this work is a sort of pre-normative study concerning flutter assessment, which could be useful to enhance the codes, as a measure of risk mitigation. The final goal is the set-up of a simplified method to estimate the flutter critical wind speed without performing wind-tunnel tests. Such a tool could be very useful for bridge engineers, especially concerning medium-span flexible bridges and/or pre-design stages. The relationship between multimodal and bimodal approach to flutter is carefully analyzed and discussed, also with the support of two case studies, and then approximate formulas retaining only three aeroelastic functions are derived. This strong simplification is validated on the basis of a wide range of structural and aerodynamic data, showing its extensive applicability. Finally, a relatively large number of flutter derivative sets are compared according to the definition of a few classes of deck cross-sectional geometry. The previously mentioned simplified formulas, reducing to three the experimental functions to be accounted for, make possible an attempt of generalization. Although this is only a first step towards this ambitious goal, it shows all the difficulties which have to be overcome but also highlights some interesting and promising results.
Flutter Vulnerability Assessment of Flexible Bridges
This work focuses on the vulnerability assessment of flexible bridges with respect to the aeroelastic instability known as flutter and two main contributions can be remarked. First, the Performance-Based Design approach is applied to the collapse limit state due to flutter. For the first time flutter derivatives are considered as random variables and the flutter problem is approached in a probabilistic way via Monte-Carlo simulations. A single-box girder deck is experimentally studied in the CRIACIV wind tunnel in order to make available data for this particular analysis. Interesting results are obtained both for this section model and for two rectangular cylinders. The second main contribution of this work is a sort of pre-normative study concerning flutter assessment, which could be useful to enhance the codes, as a measure of risk mitigation. The final goal is the set-up of a simplified method to estimate the flutter critical wind speed without performing wind-tunnel tests. Such a tool could be very useful for bridge engineers, especially concerning medium-span flexible bridges and/or pre-design stages. The relationship between multimodal and bimodal approach to flutter is carefully analyzed and discussed, also with the support of two case studies, and then approximate formulas retaining only three aeroelastic functions are derived. This strong simplification is validated on the basis of a wide range of structural and aerodynamic data, showing its extensive applicability. Finally, a relatively large number of flutter derivative sets are compared according to the definition of a few classes of deck cross-sectional geometry. The previously mentioned simplified formulas, reducing to three the experimental functions to be accounted for, make possible an attempt of generalization. Although this is only a first step towards this ambitious goal, it shows all the difficulties which have to be overcome but also highlights some interesting and promising results.
Flutter Vulnerability Assessment of Flexible Bridges
Bewertung von Flatterverwundbarkeit bei flexibeln Brücken
Mannini, Claudio (Autor:in) / Universitätsbibliothek Braunschweig (Gastgebende Institution) / Peil, Udo (Akademische:r Betreuer:in)
2006
Sonstige
Elektronische Ressource
Englisch
DDC:
624
Flutter vulnerability assessment of flexible bridges
| UB Braunschweig | 2006
| BASE | 2006
| BASE | 2006