无砟轨道聚合微粒吸声板研究

分析聚合微粒吸声材料特性,采用阻抗管试验研究吸声板厚度、材料颗粒大小、空腔设置对吸声系数的影响规律,确定聚合微粒材料的关键参数,首次采用聚合微粒材料研发一种无砟轨道降噪吸声板并确定其几何尺寸、表面设计及强度设计。提出采用拱形空腔提高吸声板的承载力且拓展其吸声频段;通过配置纤维钢筋增强吸声板的安全冗余;通过材料与结构的综合设计使吸声板兼具微孔吸声、共振吸声和干涉消声功能,增强了吸声效果。混响室试验表明,吸声板降噪系数为1.0;实车试验结果表明,测试速度为60~170 km/h时距轨道中心线25 m处吸声板降噪4.0~4.4 dB(A),降噪效果显著。

Research on Sound-Absorbing Board with Polymeric Particles for Ballastless Track

Based on the analysis of the characteristics of the polymer particle sound absorption,the influence of thickness of sound absorption board,particle size of material and cavity setting on sound absorption coefficient was studied by using impedance tube test,and the key parameters of polymer particle material was determined.For the first time,a new kind of noise reduction sound absorption board was developed by using polymer particle material for ballastless track and its geometric size,surface design and strength design was determined.The arch cavity was proposed to improve the bearing capacity of the sound absorption board and expand its sound absorption frequency band,the safety redundancy of the sound absorption board was enhanced by the configuration of fiber reinforced bars,the sound absorption board has the functions of microporous sound absorption,resonance sound absorption and interference noise elimination by the comprehensive design of materials and structures,which enhances the sound absorption effect.The reverberation room test shows that the noise reduction coefficient of the sound absorption board is 1.0.The real vehicle test results show that the noise reduction of the sound absorption board is 4.0-4.4 dB(A)when the test speed is 60-170 km/h and the distance from the track center line is 25 m,which means the noise reduction effect is significant.