车速对曲线段组合式道床系统振动特性影响分析

Analysis of Influence of Vehicle Speed on Vibration Characteristics of Combined Slab Track Systems in Curved Sections

为研究地铁车速对曲线段组合式道床系统振动特性的影响,对比分析地铁列车平均车速为20 km/h、40km/h和60 km/h工况下,曲线段组合式道床系统时域和频域的现场测试结果,分析结果表明:行车速度对曲线段组合式道床系统轨道结构垂向位移影响不大;低轨侧的轨道结构时域振动幅值均大于高轨侧;车速由20 km/h增至60 km/h时,曲线段组合式道床系统低轨侧钢轨、轨道板和隧道壁的垂向振动加速度幅值分别提升14.7 dB、7.6 dB和8.6 dB,高轨侧幅值分别提升12.2 dB、8 d B和8.4 d B;车速的提高主要增大了轨道结构63 Hz以下和250 Hz以上频段的振动,对80~200 Hz频段的振动影响不大;谐振盖板阻尼谐振器能降低组合道床在20~40 Hz频率范围内的垂向振动;车速为60 km/h时,组合式道床系统结构在1 Hz~25 Hz频段的振动显著增加,具体原因有待进一步研究。

The influence of vehicle speed on the vibration characteristics of Combined Slab Track Systems(CSTS) in curved sections is studied. The field test results in time domain and frequency domain of the curved segment of CSTS at the average speeds of 20 km/h, 40 km/h and 60 km/h were analyzed and compared. The results show that vehicle speed has little influence on the vertical displacement of CSTS structure in the curved section. The time-domain vibration amplitude of the track structure on the low rail side is larger than that on the high rail side. When the vehicle speed increases from 20 km/h to60 km/h, the vertical vibration acceleration amplitudes of the rail, track slab and tunnel wall at the low rail side of the CSTS in the curved section are increased by 14.7 d B, 7.6 dB and 8.6 d B respectively, and the amplitudes at the high rail side are increased by 12.2 dB, 8 d B and 8.4 d B respectively. The increase of vehicle speed mainly enhances the vibration of track structure in the frequency ranges below 63 Hz and above 250 Hz, and has little influence on the vibrations in the frequency range of 80 Hz-200 Hz. The resonant cover-plate damped resonator can reduce the vertical vibration of the CSTS in the frequency range of 20-40 Hz. When the vehicle speed is 60 km/h, the vibration of the CSTS track structure increases significantly in the frequency range of 1 Hz-25 Hz. The specific reasons need to be further studied.