为了研究现有嵌入式轨道在某型城际有轨电车以60 km/h速度运营时的声振特性，分别建立嵌入式轨道结构的振动和声辐射计算模型，对嵌入式轨道振动声辐射特性进行分析，了解轨道振动规律与轮轨力激励的关系。轨道振动产生的声辐射水平在中频段总体很高，在低频和高频处水平较低。通过改变轨道结构尺寸，预测各个工况下嵌入式轨道的振动和声辐射。轨道的声振特性主要表现在20 Hz～160 Hz和160 Hz～5000 Hz两个频段内，辐射声功率级在200 Hz～1200 Hz频段内表现尤为突出，应该予以特别关注。若设现有嵌入式轨道板长度为l，高为h，承轨槽宽度为w，现有PVC管直径为d，相关的参数优化表明取轨道板长度为0.75 l，高为1.25 h，承轨槽宽度为w，PVC管直径为0.88 d或者1.15 d时，轨道结构具有最优的声振特性。相关的计算能为结构设计提供很好的指导。%In order to study the acoustic and vibration characteristics of an embedded track structure when inter-city streetcars traveling at 60 km/h in the track, a model for structure vibration and noise radiation analysis was developed. The vibration and noise radiation characteristics of the embedded track were analyzed, and the relation between the vibration law and the wheel-rail force excitation was learned. The results show that the radiated sound power level induced by the track vibration is much higher in the medium frequency range than that in the low and high frequency ranges. Changing the dimensions of the track structure, the vibration and noise radiation in different working conditions were forecasted. It is found that the acoustic and vibration characteristics of the track mainly perform in two frequency ranges of 20 Hz-160 Hz and 160 Hz-5 000 Hz. The radiation sound power level appears obviously high in the range of 200 Hz-1 200 Hz, which should be cared specially. Considering an existing track structure with the slabs of length l and height h, the rail supporting groove of width w and the PVC tube of diameter d, parameters optimization shows that the structure which has slabs with 0.75 l length and 1.25 h height, rail supporting groove of w width, and PVC tube of 0.88 d or 1.15 d diameter has optimal acoustic and vibration characteristics. The concerned results can guide the design of embedded track structures.
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