Effects of Tuned Rail Damper on Track Dynamic Characteristics Optimization

Abstract

Egg-III system track is widely used in the vibration-abatement-sections of Beijing Metro, while DTVI2 fastener track is a common used form that frequently applied in the sections without vibration reduction requirements. These two railway track forms are favored in the field of urban rail transit for the respective superiorities. Recently after several months of operation, a series of abnormal problems occur, including rail corrugation problem on Egg-III fasteners section and clips fracture problem on DTVI2 rail fastening section. To provide a feasible solution for both problems, the presented paper introducing the laboratory tests which were conducted to optimize the dynamic properties of Egg-III fastener track and DTVI2 fastener track using the device of Tuned Rail Damper (‘TRD’ for short).The tests were carried out on the experimental platform in Beijing Jiaotong university, which provides dynamic testing conditions for varying track forms. To evaluate the effects of TRD on track dynamic properties, tests of direct frequency response function, vibration decay rate and vibration acceleration level were done for Egg-III system track and DTVI2 fastener track (installed/uninstalled with TRD).Experimental results indicate that TRD obviously optimizes the dynamic characteristics of both Egg-III system track and DTVI2 fastener track. The optimization effects are listed as follows: (1) The resonance peaks of frequency response function curve are significantly reduced and moved in the range of 100-400Hz, which is identified as the cause of the rail corrugation occurred on Egg-III system track sections. (2) The vertical and transverse vibration decay rates on Egg-III system are obviously increased with TRD， suppressing the vibration transited along the rail. (3) Vibration reduction ability of Egg-III system track is not weakened with TRD, but strengthened up to 1.2-6 times at most frequencies. (4) The amplitudes of frequency response function curve are reduced when TRD was installed on the rail of DTVI2 fastener track. (5) The vertical and transverse vibration decay rates of DTVI2 fastener track are raised markedly with TRD, that the vibration energy transmitted to rail fastening clips is reduced.