Analysis of a Shear beam model with suspenders in thermoelasticity of type III
Meriem Chabekh, Nadhir Chougui, Delfim F. M. Torres
TL;DR
The paper addresses the dynamic response of a suspension-bridge roadbed modeled as a 1D extensible thermoelastic shear beam with suspenders under thermoelasticity of type III. It combines rigorous analysis with a practical numerical framework: global well-posedness and exponential stability are established via Faedo–Galerkin approximations and Lyapunov functionals, while a fully discrete finite element scheme with backward Euler time stepping is shown to be energy-stable and convergent with an error bound of $O(h^2+(\Delta t)^2)$ under high regularity. The results yield robust long-time behavior guarantees and provide concrete discretization guidance supported by numerical simulations that illustrate energy decay and convergence. This work provides a solid mathematical and computational foundation for stable simulations of large-span bridges under coupled thermoelastic dynamics and suspender interactions.
Abstract
We conduct an analysis of a one-dimensional linear problem that describes the vibrations of a connected suspension bridge. In this model, the single-span roadbed is represented as a thermoelastic Shear beam without rotary inertia. We incorporate thermal dissipation into the transverse displacement equation, following Green and Naghdi's theory. Our work demonstrates the existence of a global solution by employing classical Faedo-Galerkin approximations and three a priori estimates. Furthermore, we establish exponential stability through the application of the energy method. For numerical study, we propose a spatial discretization using finite elements and a temporal discretization through an implicit Euler scheme. In doing so, we prove discrete stability properties and a priori error estimates for the discrete problem. To provide a practical dimension to our theoretical findings, we present a set of numerical simulations.
