Comfort degree analysis on metro vibration isolation based on 1/3 times frequency course spectrum

Analysis program of vibration comfort degree was compiled based on several calculation methods such as Fast Fourier Transform method, 1/3 times frequency course spectrum and vibration acceleration level. Story acceleration under subway vibration was calculated according to one multi-tower structure with an enlarged base located above the subway tunnel Elastic time-history method was used and favorable factor such as initial vertical stiffness was considered. Story acceleration time-history curve was changed into decibel by program of vibration comfort degree and comfort degree was evaluated according to limit values of national codes. The results of elastic time-history method show that the effect of reducing noise under subway vibration is fine. Peak values of story acceleration decrease obviously and are lower than limit values.