Energy harvesting analysis in railway bridges: an approach based on modal decomposition

Abstract

In this paper the authors investigate the energy harvesting in railway bridges and analyse the performance under different operational conditions. An approximation based on modal superposition is proposed for the computation of the energy harvested from train-induced bridge vibration. This approach is consistent with the analytical modal solutions of the simply-supported Bernouilli-Euler beam transverse response under moving loads. The influence of the bridge maximum dynamic response and cancellation phenomena, the tuning effect of the harvester device and the relevance of different modal contributions on the harvested energy are studied using a single-degree of freedom system as a simplistic mechanical approach. Later, a piezoelectrically coupled lumped parameter model is used to investigate the available energy due to High- Speed train passages at different circulating speeds. Finally, the feasibility of energy harvesting is evaluated from the experimental data measured by the authors in a railway bridge from the Madrid-Sevilla High-Speed line. The obtained results allow quantifying the harvested energy in a time window of three and a half hours and twenty train passages.