Calculation of the modal parameters of a suspension bridge
Updated 8 May 2020
The calculation of the eigenfrequencies and mode shapes of a suspension bridge using the present Matlab code is based on the theory of continuous beam and the theory of shallow cables. The mode shapes are obtained using Galerkin's method where a series expansion is used. The method was first applied by Sigbjörnsson & Hjorth-Hansen . E. Strømmen  expanded their works to the vertical and torsional motion.
The bridge is represented as a horizontal streamlined beam, where the z-axis is the vertical axis, the y-axis is the along-beam axis and the x-axis is the cross-beam axis. The three motions of interests (lateral, vertical, and torsional) and both symmetric and asymmetric modes are computed.
- eigenBridge is a function that computes the mode shapes and eigenfrequencies of the suspension bridge
- Documentation.mlx: is an example of the application of this function
 Sigbjönsson, R., Hjorth-Hansen, E.: Along wind response of suspension bridges with special reference to stiffening by horizontal cables. Engineering Structures 3, 27-37 (1981)  Structural Dynamics, Einar N Strømmen, Springer International Publishing, 2013. ISBN: 3319018019, 9783319018010 Characteristics of the single-span suspension bridge
Cheynet, E. Calculation of the Modal Parameters of a Suspension Bridge. Zenodo, 2020, doi:10.5281/ZENODO.3817982.
MATLAB Release Compatibility
Platform CompatibilityWindows macOS Linux
Inspired: Automated vehicle identification using bridge vibrations, Static analysis - Suspension bridge - A benchmark solution, Buffeting response of a suspension bridge (time domain), Mode shapes extraction by time domain decomposition (TDD), Flutter velocity of a suspension bridge, Dynamic response of a line-like structure to a random load, Buffeting response of a suspension bridge (frequency domain), Linear vertical vibrations of suspension bridges
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!Start Hunting!
See release notes for this release on GitHub: https://github.com/ECheynet/eigenBridge/releases/tag/v3.3
Added the project website
-Example file provided + many simplifications
- possibility to use a different young modulus for main cables
- separation into more modules for sake of clarity (new matlab file "ExampleBridge.m" included)