轨道交通混凝土箱梁低频噪声贡献源及空间分布

以轨道交通双线混凝土简支箱梁为研究对象,建立车辆-轨道-箱梁有限元模型和箱梁振动-辐射噪声有限元-无限元模型。结合现场试验,计算了箱梁整体和各板件的声场分布及各板件的声压贡献。结果表明,有限元-无限元模型能够准确预测箱梁的结构噪声;腹板对梁侧声压贡献较小;近场声压主要受底板的影响,其次是翼板;远场声压主要受底板和顶板的影响;在底板以下空间,底板对声场起控制作用;箱梁同一高度,顶板声压贡献略大于翼板,两者起主要作用;顶板以上区域,顶板声压贡献远大于其他板件。

Contribution Source and Spatial Distribution of Concrete Box Girder Low-frequency Noise in Rail Transit

By taking double-line concrete simply supported box girder of rail transit as the research object, a vehicle-track-box girder finite element model and a box girder structure-borne vibration-radiation noise finite element model-infinite element model were established. Combined with field tests, the sound pressure distribution of whole box girder and each plate was obtained by the model, and the sound pressure contribution of each plate was analyzed. The results show that the finite element-infinite element model can accurately predict box girder structure-borne noise. The contribution to the sound field of web plate is less. The sound pressure of the near field is mainly affected by bottom plate, followed by wing plate. The sound pressure of the far field is mainly affected by bottom plate and top plate. In the space below bottom plate, the noise radiated by bottom plate dominates the sound field. At the same height of the box girder, the sound pressure contribution of roof plate is slightly larger than wing plate, and these two plates play a major role. In the area above roof plate, the sound pressure contribution of roof plate is much larger than other plates.