摘要
以成都—都江堰高速铁路工程为背景,通过现场测试试验,研究桥上无砟轨道铺设橡胶减振垫的减振效果。结果表明:铺设橡胶减振垫后,减振垫上钢轨和轨道板的振动略有放大,但影响甚微,而减振垫下底座板、桥梁及地面的振动显著降低,其中底座板的最大振动加速度降低了85%左右;时域内,在距线路中心线0,15和30m处地面的最大竖向加速度振级均降低了9.5dB左右;频域内,在0～6.3Hz频段内,橡胶减振垫的减振效果不明显;在8～20Hz频段内,由于与轨道—桥梁—大地系统本身的自振频率重合,反而放大了地面的振动;在25～100Hz频段内,减振作用明显,且距线路中心线越远,减振效果越显著,但距线路中心线不同距离处对应最大减振作用的频段和插入损失值不同,0m处最大减振作用出现在31.5Hz频段,插入损失值为7.8dB,15和30m处最大减振作用均出现在40Hz频段,插入损失值分别为13.6和16.4dB。可见,橡胶减振垫能够对25Hz以上频段的振动起减振作用。
With Chengdu-Dujiangyan high-speed railway as engineering background, the damping effect of rubber absorbers for ballastless track on viaduct was studied by field test. The results show that after laying rubber absorbers, the vibrations of rails and track slabs above rubber absorbers have been slightly enlarged, but the impact is very little. And the vibrations of base plate, bridge and ground below rubber absorbers have been significantly reduced, among which, the maximum vibration acceleration of base plate is reduced about 85%. In time domain, at the points 0, 15 and 30 m away from the central line of the track, the maximum vertical acceleration levels of ground vibration have been all reduced about 9. 5 dB. In frequency domain, in the frequency range of 0-6.3 Hz, the damping effect of rubber absorber is not obvi- ous. In the frequency range of 8-20 Hz, however, the ground vibration has been enlarged due to the superposition of the natural vibration frequency of track-bridge-ground system itself. In the frequency range of 25-100 Hz, the damping effect is significant, and the farther away from the central line, the more significant is the damping effect. Nevertheless, different distances away from the central line of track, the frequency ranges and insertion loss values corresponding to the maximum damping effect are different. 0 m away from central line, the maximum damping effect appears in the frequency range of 31.5 Hz, and the value of insertion loss is 7.8 dB. 15 and 30 m away from the central line, the maximum damping effects of both appear in the frequency range of 40 Hz, and the value of insertion loss is 13.6 and 16.4 dB respectively. It can be concluded that rubber absorbers can reduce the vibrations above the frequency range of 25 Hz.
出处
《中国铁道科学》
EI
CAS
CSCD
北大核心
2013年第4期8-13,共6页
China Railway Science
基金
国家自然科学基金资助项目(51008256)
铁道部科技研究开发计划项目(2011G009)
关键词
无砟轨道
桥梁
橡胶减振垫
减振
竖向加速度
振级
Ballastless track Bridge
Rubber absorber
Vibration attenuation
Vertical acceleration
Vibration level
