Faculté des Sciences appliquées
Faculté des Sciences appliquées

Effet du couplage modal sur le contrôle du comportement vibratoire de passerelles

Loore, Thibault ULiège
Promotor(s) : Denoël, Vincent ULiège
Date of defense : 25-Jun-2018/26-Jun-2018 • Permalink :
Title : Effet du couplage modal sur le contrôle du comportement vibratoire de passerelles
Translated title : [en] Effect of modal coupling on the control of the dynamic behavior of footbridges
Author : Loore, Thibault ULiège
Date of defense  : 25-Jun-2018/26-Jun-2018
Advisor(s) : Denoël, Vincent ULiège
Committee's member(s) : De Ville De Goyet, Vincent ULiège
Duchene, Yves 
Language : French
Number of pages : 100
Keywords : [fr] Passerelles
[fr] Couplage modal
[fr] Inerter
[fr] Théorie des perturbations
[fr] Fonctions de transfert
[en] Modal coupling
[en] Inerter damper
[en] Perturbations theory
[en] Transfer function
[en] footbridges
Discipline(s) : Engineering, computing & technology > Civil engineering
Target public : Researchers
Professionals of domain
General public
Institution(s) : Université de Liège, Liège, Belgique
Degree: Master en ingénieur civil des constructions, à finalité spécialisée en "civil engineering"
Faculty: Master thesis of the Faculté des Sciences appliquées


[en] Modern footbrigdes are lightweight and flexible structures that have to meet strict comfort criteria as far as their acceleration levels under dynamic loading are concerned. Given their slenderness, external dampers are a typical solution to keep these accelerations under thresholds. The most commonly used damping devices are tuned mass dampers (TMD). One of their main limitation though is their allowed mass. Furthermore, their design is usually based on simplifying asumptions that do not account for modal coupling. Yet, this can have a significant impact on their dynamic response, especially when eigen frequencies are closely spaced.

This paper investigates the viability of a new damping technology for harmonic loading, in the instance of inerter dampers. It is shown that they outperform conventional TMD thanks to their mass amplification effect. Then, modal coupling is studied by means of a mathematical method coming from perturbations theory. This allows to set up a closed-form expression for the transfer matrix of a coupled system. This one is general, simple, but meaningful. This tool is then used to derive analytical elementary expressions for the coupled or uncoupled design of dampers. The basic understanding of modal coupling also enables a totally new approach proposing to use only one damper to control two closey-spaced modes of vibration. Applicability criteria for the method as well as the parameters to be provided for the damper and its suitable positions are also derived in an analytical manneer. The use of inerter dampers appears very convenient for the purpose of this method. The latter is finally applied on a real-life case study and happens to be competitive with conventional damping techniques (use of 2 dampers for 2 modes).



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  • Loore, Thibault ULiège Université de Liège > Master ingé. civ. constr., fin.


Committee's member(s)

  • De Ville De Goyet, Vincent ULiège Université de Liège - ULiège > Département ArGEnCo > Conception, calcul et exécution des structures except.
    ORBi View his publications on ORBi
  • Duchene, Yves Bureau Greisch
  • Total number of views 46
  • Total number of downloads 100

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