Control of Train-Induced Vibration Using Periodic Materials

With the rapid development in megacities, useable lands for construction are in short supply. The upper space above the garage of subways is considered a potential land source for megacities. However, interference from the train-induced vibration has not been properly solved. The existing vibration controls have been applied to the railway fastener, floating slab, and sleeper, yet these facilities suffer from some drawbacks. This study mainly discusses the feasibility of a new type of material, i.e., periodic material, in reducing the train-induced vibration. The periodic material is a kind of material that has the characteristic of frequency band gaps. In other words, the train-induced vibration wave with a frequency falling into the frequency band gap of the designed periodic materials can be dramatically attenuated. The train-induced frequency of elastic stress waves affecting the super-structure is considered to be in the range of 30–80 Hz according to the reported acceleration spectrum obtained from the subway vibration experiments. The vibration reduction by using periodic materials in a variety of structural forms and material properties was evaluated through numerical simulation. It is found that the vibration in the considered frequency range can be effectively reduced by using periodical material, which is a better solution than the existing damping methods.