线下式桥建合一车站振动噪声特性及控制研究

Research on the Vibration and Noise Characteristics and Control of the Under-line Bridge-construction Integration Station

研究目的:为掌握线下式车站车致振动和噪声的形成机理、传递路径及分布特性差异,建立“列车-轨道-结构-土体”耦合动力学模型研究列车过站时引发的站房车致振动,利用声学有限元方法计算二次结构噪声,利用统计能量分析计算站厅内环境噪声,并根据研究结果开展线下式桥建合一车站低振动噪声设计。研究结论:(1)相比桥建分离车站,桥建合一车站候车厅在30 Hz以上的振级增幅达30 dB,而在人体更敏感的30 Hz以下低频范围内振级差异仅3.5 dB;(2)桥建合一车站因其承轨层与周边结构硬连接,承轨层振动更小,二次结构噪声较桥建分离车站低5.5 dBA,环境噪声低1.4 dBA,总体上对乘客来说具有更好的声振舒适性;(3)采用重型减振轨道能够有效抑制站房振动,楼板的垂向振动加速度减小10倍以上,二次结构噪声降幅可达25 dBA以上;在站台层和站厅层内采取吸声、隔声措施可使候车厅内环境噪声降幅达15 dBA以上;(4)相关振动噪声控制方案可为综合交通枢纽的减振降噪设计提供参考。

Research purposes:In order to understand the formation mechanism,transmission path and distribution characteristics of vehicle-induced vibration and noise in the under-line station,a ′train-track-structure-soil′ coupling dynamic model was established to study the vehicle-induced vibration of the station caused by the train passing through the station.The acoustic finite element method was used to calculate the secondary structure noise,and the statistical energy analysis was used to calculate the environmental noise in the station hall.The low vibration noise design of the under-line bridge-construction integration station was carried out according to the research results.Research conclusions:(1) Compared with the bridge-construction separation station,the vibration level of the waiting hall of the bridge-construction integration station increases by 30 dB above 30 Hz,while the difference of vibration level is only 3.5 dB in the low frequency range below 30 Hz,which is more sensitive to human body.(2) Due to the hard connection between the bearing layer and the surrounding structure,the vibration of the bearing layer of the bridge-construction integrated station is smaller.The secondary structural noise is 5.5 dBA lower than that of the bridge-construction separated station,and the environmental noise is 1.4 dBA lower than that of the bridge-construction separated station.In general,it has better acoustic and vibration comfort for passengers.(3) The use of heavy damping track can effectively suppress the vibration of the station building.The vertical vibration acceleration of the floor is reduced by more than 10 times,and the noise reduction of the secondary structure can reach more than 25 dBA.The sound absorption and insulation measures in the platform layer and the hall layer can reduce the environmental noise in the waiting hall by more than 15 dBA.(4) The relevant vibration and noise control schemes can provide reference for the vibration and noise reduction design of integrated transportation hubs.