高速列车内地板隔音垫声学特性的研究

通过数值方法，以传递矩阵法建立车内地板声学模型，研究隔音垫不同材料参数和厚度对内地板隔声量的影响，分别考虑了在不同弹性模量、密度、阻尼系数以及随厚度变化的情况下，内地板隔声量的变化规律，然后确定隔声性能优越的隔音垫材料类型和结构型式。结果表明，有、无隔音垫，内地板隔声量的变化较大，铺设1 mm隔音垫与无隔音垫比较，内地板计权隔声量提高约5 dB；另外，隔音垫厚度对整个内地板隔声量影响也较大，隔音垫厚度每增加1 mm，内地板计权隔声量提高1 dB ～3 dB；隔音垫材料参数对整个内地板隔声量影响不大，弹性模态改变一个数量级，阻尼系数相差0.02，内地板隔声量几乎无影响。

Effect of Sound Insulation Pad on Sound Transmission Loss Property of Interior Floor of High Speed Trains

The acoustic model of interior floor of high speed trains is established based on the transfer matrix method.The influence of elastic modulus,density,damping coefficient and thickness of the sound insulation pad on the transmission loss of the interior floor is studied.The results show that（1） sound insulation pad has large effect on the transmission loss of the interior floor.Comparing with the floor without sound insulation pad,the weighted sound insulation effect of the floor with 1mm thick pad can be increased by 5 dB;（2） the thickness of the sound insulation pad has a great influence on the transmission loss of the interior floor.When the sound insulation pad thickness is additionally increased by 1 mm,the weighted sound transmission loss of the interior floor can be increased by 1 dB -3 dB;（3） the material parameter of the sound insulation pad has little influence on the sound transmission loss of the floor.For example,0.02 change of damping coefficient will cause nothing in the change of the sound insulation of the floor.