Project
Mitigation of railway induced vibration using seismic metamaterials
Railways are a sustainable and climate-friendly means of transport, but vibration remains an environmental concern. We will investigate if seismic metamaterials installed on the propagation path between tracks and buildings can efficiently mitigate railway-induced vibration. Seismic metamaterials are artificially engineered composite materials consisting of an arrangement of cells that are installed on the surface or embedded in the soil; examples are tuned resonators or trees. At the subwavelength scale, the interaction of surface waves with these local resonators may result in band gaps, where wave propagation is impeded or in the conversion of surface waves into bulk shear waves. At higher frequencies, the structural periodicity may also result in bandgap creation. Very promising results were recently reported protecting important civil infrastructure from earthquakes. We will investigate if seismic metamaterials can also be employed to mitigate railway induced vibration under realistic conditions involving broadband excitation, moving loads, and layered soils. This will be based on numerical analysis with state-of-the-art models, a parametric study to clarify underlying physical principles, and an in situ demonstration test along the HST line Brussels-Koln. We will check if a better efficiency can be obtained over a broader frequency range and spatial area, and at a lower construction cost than with stiff wave barriers.