Experimental Validation of Piezoelectric Energy-Harvesting Device for Built Infrastructure Applications

Vibration energy-harvesting devices are increasingly becoming more efficient and useful. The performance of such devices for energy harvesting from vibrations of civil infrastructure can be theoretically quantified, and energy harvesting under harmonic loadings can be validated experimentally. Experimental validation of such devices for civil infrastructure applications, such as bridges, remains an important but more complex and challenging issue, in part due to the more uncertain nature of the dynamic response of structures under operational conditions and problems with access for such testing. Lack of existing experimental benchmarks is also a major obstacle behind adopting this technology for bridges. This study presents a laboratory-based experimental procedure through which a piezoelectric energy harvester was experimentally verified for rail bridges in their operational condition with trains traversing them. A general experimental arrangement required for validating a piezoelectric cantilever energy-harvesting device is presented, along with the fabrication of a prototype device and detailed experimental setup. A model bridge undergoing loadings from an international train fleet was chosen, and the acceleration response from the bridge was used as the excitation source for the energy-harvesting device. Numerically estimated performances of the energy harvester were validated by experimentation for a range of trains. The method is applicable for validating energy harvesting from arbitrary vibrations of built infrastructure within the laboratory environment without the need of scaling. The device and related experimental procedure will serve as a benchmark for similar unscaled tests within a laboratory environment and can be useful for assessing devices or their applications in monitoring built infrastructure under realistic conditions without the need for deployment on site.