高速铁路桥上新型声子晶体声屏障车致振动研究OA

With the continuous increase in the operating speed and frequency of high-speed railway trains,controlling the acoustic environment along the lines has become significant challenges.Installing noise barriers on both sides of the tracks is one of the most effective methods for mitigating vehicle-induced vibration and noise.Given the remarkable advantages of acoustic metamaterials and phononic crystals in sound insulation,the design of novel noise barriers based on phononic crystals can effectively enhance their acoustic performance.This approach is capable of satisfying the demands for acoustic environment quality control along high-speed railway lines.However,the transmission of vibration energy generated by moving trains would cause the sound barrier to vibrate,thereby affecting its service performance and noise reduction efficiency.Therefore,it is necessary to conduct a systematic study on the train-induced vibration issues of high-speed railway noise barriers.First,the prediction model for train-induced vibrations in existing vertical noise barriers on high-speed railway bridges was established,and the accuracy of the developed theoretical model was verified through field test.Based on this,a new prediction model for train-induced vibrations in phononic crystal noise barriers on bridges was developed,and the train-induced vibration characteristics of the novel phononic crystal noise barriers were investigated.The results indicate that the lateral vibration of the novel phononic crystal noise barrier is consistently stronger than its vertical vibration.Compared to the existing vertical noise barrier,the peak vertical vibration in the time domain at the shell position of the novel phononic crystal noise barrier is reduced by 36.77%,and its dominant vertical vibration frequency range is narrowed from 0―120 Hz to 0―90 Hz.The height of the phononic crystal unit cell significantly influences the vibration of the novel barrier.Therefore,unit cells with lower heights and multi-unit panel configurations should be adopted in the novel phononic crystal noise barrier,as this strategy holds significant advantages in mitigating the train-induced vibration characteristics of the noise barrier.