Existence of torsional solitons in a beam model of suspension bridge

TL;DR

This paper proves the existence of stable torsional solitons in a suspension bridge model, highlighting their potential impact on bridge stability and safety.

Contribution

It demonstrates the existence of torsional solitons in a degenerate plate model of suspension bridges, including conditions for nontrivial torsional components.

Findings

Existence of solitons in the bridge model.

Torsional components appear under large tension.

Relevance to suspension bridge stability and safety.

Abstract

This paper studies the existence of solitons, namely stable solitary waves, in a suspension bridge. The bridge is modeled as a degenerate plate, that is, a central beam with cross sections, and displays two degrees of freedom: the vertical displacement of the beam and the torsional angles of the cross sections. Under fairy general assumptions, we prove the existence of solitons. Under the additional assumption of large tension in the sustaining cables, we prove that these solitons have a nontrivial torsional component. This appears relevant for the security since several suspension bridges collapsed due to torsional oscillations.