Optimal Time-Frequency Distribution for Analyzing Non-Stationary Signal of Ground Vibration Induced by Subway
Vibrations induced by subways can cause discomfort to residents, mismatch of sensitive equipment and even damage to dilapidated structures.Ground vibration responses may be processed as weakly stationary signals during the whole time history, while its detail (local information) shows significant non-stationary characteristics.Time-frequency analysis has been proved to be an efficient mean to clarify the non-stationary characteristics.Firstly, in-situ measurement of ground vibrations induced by subways was carried out.Then, Wigner-Ville distribution, Pseudo Wigner Ville distribution and Page distribution were used to analyze the acquired acceleration responses da ta, respectively.Energy concentration index was defined to evaluate the time-frequency localization performance of each distribution.Compared results showed that Page distribution had better timefrequency energy concentration than the other two.Furthermore, localization energy generated by each pass-by subway car, which was corresponding to different segment of the whole sample, was analyzed by Page distribution.The results indicated the energy ratio, which was the ratio of energy mainly produced by pass-by car to that of the overall time-frequency window, is similar for each segment.Finally, the decay tendency of time-frequency localization energy along with the distance to the track-center was studied.
ground vibration non-stationary process time-frequency distribution localization energy energy concentration index
B.Zhang G.Zong W.T.Li T.T.Shan
Research Institute of Structural Engineering and Disaster Reduction, Tongji University, Shanghai, China
国际会议
第六届国际环境振动学术研讨会(6th International Symposium on Environmental Vibration)(ISEV2013)
上海
英文
81-87
2013-11-08（万方平台首次上网日期，不代表论文的发表时间）