混凝土箱梁在列车动荷载作用下会产生振动进而辐射低频结构噪声,影响沿线居民生活品质。以一跨高速铁路32m双线混凝土简支箱梁为研究对象,对箱梁板厚、翼缘斜撑、翼缘横隔板对结构噪声的影响进行研究。首先,基于车辆-轨道-桥梁系统频域模型求解扣件力;然后,将频域扣件力施加在桥梁-轨道有限元模型中进行谐响应分析求解箱梁振动。最后,利用边界元法以节点位移为边界条件求解桥梁结构噪声最大声压级。结果表明:在满足受力的前提下适当增加板厚可有效降低桥梁结构噪声;增加腹板厚度桥梁结构噪声降噪量最好,腹板厚度增大4 cm时结构噪声减小3 d B(A)~5 d B(A);设置翼缘斜撑可降低桥梁结构噪声约10 d B,斜撑间距4 m为宜,而对A计权声压级降噪效果不明显;设置翼缘横隔板可降低结构噪声约9 d B,三角隔板和弧角隔板降噪效果相当。
In recent years, there has been rapid growth of Chinese rail transit networks. Many of these networks require elevated bridges. This results in a bridge-borne noise source, which occurs in addition to the main noise source(i.e., wheel–rail interactions). Bridge-borne noise is attracting increasing attention because of its low-frequency noise characteristics. This review paper first analyzes the space distribution, spectral characteristics, and sound pressure levels of noise radiated by all-concrete, steel–concrete composite, and all-steel bridges, mainly according to experimental studies. Second, this paper reviews existing theoretical prediction models of noise emanating from bridges: the semianalytical method, the Rayleigh integral method, the boundary element method, and statistical energy analysis. Several case studies are reviewed, and their results are discussed. Finally, according to the results of the current review, the main factors affecting bridgeborne noise are analyzed, several noise reduction measures are proposed for different types of bridges, and their effectiveness is demonstrated.
