Study On The Sound Insulation Of Floor Of High-Speed Train And Its Improvement Methods

Based on the analysis of the floor structure of high speed train, study on sound insulation characteristics and methods of its improvement are conducted. Specific contents as follows:First of all, the influences of inner floor, soundproof mat and winter protection material to the sound insulation characteristics of floor structure are studied though tests:Wood floor contributes more in low frequencies, while sandwich aluminum floor is more favorable to higher frequencies. When the soundproof mat is add to the floor structure, sound insulation levels in all frequencies grow and the anastomosis valley gets reduced. By the way, the heavier the soundproof mat is, the more sound insulation in low frequencies grows, while under the effects of various factors, the influences of soundproof mat to sound insulation in higher frequencies is not clear. The sound absorption characteristics of winter protection material give a certain impact on sound insulation of floor structure, but not very big.Secondly, aimed to find out the methods of sound insulation improvement of inner floor or outer floor, tests and simulations are conducted in three aspects:The sound insulation effect on inner floor with different adhesion forms of soundproof mat is studied and it has been proved that closer adhesion form will be more benefit to carrying out the damping characteristics of soundproof mat, as well as the improvement of sound insulation. Sound insulation effect to aluminum profile outer floor with different damping layer thickness is studied and show that the sound insulation will grow with the thickness of damping layer increase, but the mass and can space must be under permission. The sound insulation effect of aluminum profile outer floor filled up with absorption material in its cavities is studied and find out that sound insulation grows much more with the filling of absorption material. Then in order to study the effect of damping layer with different thickness to the structure-borne propagation of aluminum profile outer floor though the tests of structure damping characteristics and sound and vibration characteristics, respectively.At last, give some suggestions to improve the sound insulation of floor structure, and tentatively proposed the high sound insulation floor structure of high speed train.