摘要
采用锤击法,对梯形轨道系统(简称梯轨)进行动力特性试验。利用变时基传递函数细化分析方法,解决力信号时域波形精度与加速度信号频率分辨率之间的矛盾,提高低频脉冲频响分析精度。根据锤头材料的锤击特性和试验研究的频率范围,分别选择尼龙和钢制锤头进行梯轨模态和减振特性试验研究。结果表明:梯轨的低阶模态分布比较密集,基频为48.6Hz,前3阶模态的阻尼比较高,1阶阻尼比最大,达到6.64%;梯轨的工作频率约为50Hz,在梯轨工作频率之上1/3倍频程中心频率处,传递损失不随锤击力的大小而变化,梯轨的振动衰减系数为常数;梯轨具有较高的减振作用,在0～1000Hz频段传递损失在45dB左右。
By means of hammering method, tests were carried out on the dynamic characteristics of the ladder track system. By making use of the varied-time-base transfer function detailed analysis method, the conflict between the accuracy of the time-domain waveform and the frequency resolution of the acceleration signal of the ladder track system was solved, which improved the analysis precision of the low frequency response. By analyzing the hammering characteristics of different hammerheads and the sample frequency, nylon and steel hammerheads were chosen to make the mode and vibration mitigation experiment respectively. The result shows that the low mode distribution of ladder track is intensive, the first-order natural frequency of the ladder track system is 48.6 Hz, the former three orders of modal damping ratio are higher and the first-order is the largest, reaching 6.64%. The work frequency of ladder track is about 50 Hz.The vibration attenuation coefficient of ladder track is a constant above the work frequency of the ladder track in the one-third octave. There is a high vibration mitigation effect of the ladder track,the transfer loss is about 45 dB through 0～1 000 Hz.
出处
《中国铁道科学》
EI
CAS
CSCD
北大核心
2010年第2期24-28,共5页
China Railway Science
基金
国家自然科学基金资助项目(50848046
50538010)
关键词
城市轨道交通
梯形轨道
动力特性
锤击法
变时基
传递损失
试验研究
Urban mass transit
Ladder track
Dynamic characteristics
Hammering method
Varied-time-base
Transfer loss
Experimental study
