Study On Vibration Isolation Performance Of Floting Slab Track

Undergroud railways are becoming more and more popular nowadays in our cities, while the problem of vibration and sound brought by the metro is also a very big deal. There has a very effective way to reduce the vibration and sound, that is the floating slab track (FST).The basic theory of floating slab track is to add a mass-spring system with very low nature frequency between the rail and the infrastructure to isolate the vibration from the infrastructure.Though some methods have been developed to analyze the isolation performance of floating slab track, but some shortages still exist.Firstly, generally the analysis to the FST is simplified to a system with one degree of freedom and the dynamic characteristic of the rail and the floating slab are not considered. thus the analysis to the FST is not so accurate.Secondly, the excitation is simplified as a simple harmonic stimulation and the dynamic characteristic of the vehicle is also not considered.For the first problem, we have developed the single and double infinity Euler beam for the FST systems. The single Euler beam is for the FST system with short floating slab and the double Euler beam is for the FST system with long floating slab.Fro the second problem, the coupled vehicle-rail model can also be used in the FST systems. We couple the vehicle, rail and the floating slab together here and form a full method to calculate the behavior of the FST. Because of the complexity of the problem, the way to deal with four order partial differential equation is also described in this paper. For single Euler beam, we will solve the equation by the method of boundary condition and for the double Euler beam, we will solve the equation by the method of Laplace transformation.A series of detailed analysis to the result of the calculation is the main point of the paper. We investigate how the parameters of FST influence the isolation performance of the FST and we will give some advice to the parameter design of FST. A stimulation calculation will be given to verify the design steps from the advice.Above all, the emphases and innovations of this paper are: continuous model is developed to model the FST, coupled calculation of the vehicle, rail and floating slab, solve the high order partial differential equation in frequency domain, find how the parameters of the FST influence the behavior of the FST system, and the suggestion to the steps of FST parameter design is given.