Analysis on Vibration Reduction Characteristics of Ladder Track Structure on Metro Viaduct under Measured Track Irregularities

摘要

3D FEM models of ladder track and rail-bearing platform track on metro viaduct were established to analyze the vibration reduction characteristics of ladder track structure.Based on track irregularities measured by track inspection car, time-history vertical accelerations of rail, sleeper, flange and beam bottom were solved to contrast the dynamic characteristics of the two track structure.Results show that the vibration level of rail and sleeper are higher on ladder track than on rail-bearing platform track, and the vibration reducing effect of ladder track for flange and beam bottom mainly embodies in frequency range of 1～40Hz in which average vibration reduction values on flange and beam bottom are 28dB and 22dB, with maximum values 40dB and 33dB.The results can provide reference for design of ladder track as well as its application in metro line.