The Analysis And Study Of High-speed Train Floor’s Sound Insulation Property

To reduce the track noise transmission into carriages of high-speed train, it’s essential to study the sound insulation property of high-speed train floor. The article analyses the typical structure of high-speed train floor. The sound insulation property of high-speed train’s inner floor and external floor is analyzed and studied. I have studied the impact on sound insulation property of high-speed train’s external floor when it’s filled with sound absorptive materials. All the study work is to provide reference for the optimization design of the high-speed train’s floor structure.According to the layered structure characteristic of high-speed train’s inner floor, some plates’ sound insulation properties are analyzed, which contain single-layer aluminum sheet, sound insulating pad and honeycomb panel. It’s indicated that single-plate sound insulation property is mainly decided by mass law. The side length of single-plate only affects its sound insulation property below and around the first resonant frequency. The soun d insulation property of honeycomb panel can be improved significantly when the thickness of aluminum sheet in honeycomb panel is increased. The sound insulation property of honeycomb panel can be improved when the thickness of interlayer in honeycomb panel is increased. Compared with single-layer aluminum sheet, when the aluminum sheets have same total thickness, honeycomb structure can improve the sound insulation property of single plate. Using the method of wave transfer, three-layer plate’s sound insulation property of structure that consists of two aluminum sheets with air between them is analyzed.In terms of space harmonic expansion approach, external floor sound insulation property is analyzed and studied. The relationship between sound insulation property and vibration performance of external floor is analyzed. The trend of external floor’s sound transmission loss curve is the result of two plates’ vibration. The external floor ’s optimization design is also studied. My study shows that external floor is most effective in insulation when the sound wave is vertical to the panel. There exists the best angle between rib plate and face plate. It’s conducive to improving comprehensive properties of external floor when the thickness of rib plate is increased. The variation of external floor’s total thickness and face plates’ thickness can make external floor’s comprehensive properties’ evaluation index move among different frequency ranges. Appropriate thickness can be chosen in accordance with the need to optimize the specific frequency range. The achievements will provide reference for the optimization design of the high-speed train’s external floor structure.The sound insulation property of external floor filled with sound absorptive materials is analyzed and studied. The impact on sound insulation property of external floor filled with sound absorptive materials is studied. Sound absorptive materials affect sound insulation property of external floor for its stiffness and mass. With the increasing total thickness of external floor,the stiffness of rib plate decreases, and sound absorptive materials is more remarkable in the impact on sound insulation property of external floor. The rib plate’s stiffness of high-speed train is relatively larger, while the stiffness and mass of sound absorptive materials is relatively smaller, as a result, sound insulation property of external floor filled with sound absorptive materials has no significant improvement.