A qualitative explanation of the origin of torsional instability in suspension bridges. (July 2015)

• Record Type: Journal Article
• Authors: Berchio, Elvise; Gazzola, Filippo
• Is Part Of: Nonlinear analysis. Volume 121(2015)
• Page Start: 54
• Page End: 72
• Publication Date: 2015-07
• Subjects: 37C75 -- 35G31 -- 34C15; Suspension bridges -- Torsional stability -- Hill equation; Mathematical analysis -- Periodicals; Functional analysis -- Periodicals; Nonlinear theories -- Periodicals; Analyse mathématique -- Périodiques; Analyse fonctionnelle -- Périodiques; Théories non linéaires -- Périodiques; Functional analysis; Mathematical analysis; Nonlinear theories; Periodicals; Electronic journals; 515.7248
• DOI: 10.1016/j.na.2014.10.026
• Languages: English
• ISSNs: 0362-546X

Abstract

Abstract: We consider a mathematical model for the study of the dynamical behavior of suspension bridges. We show that internal resonances, which depend on the bridge structure only, are the origin of torsional instability. We obtain both theoretical and numerical estimates of the thresholds of instability. Our method is based on a finite dimensional projection of the phase space which reduces the stability analysis of the model to the stability of suitable Hill equations. This gives an answer to a long-standing question about the origin of torsional instability in suspension bridges.