调频式钢轨阻尼器对曲线轨道动力特性影响研究

The influence of the tuned rail damper(TRD)on the dynamic response of the curved track

建立垂向安装有具有两阶自振频率的调频式钢轨阻尼器(Tuned Rail Damper,TRD)的曲线轨道频域解析模型。将此曲线轨道视为离散支承的无限周期结构,引入周期无限结构理论,结合频域模态叠加法,通过求解轨道某“基本元”内一点的动力响应,进而得到安装有TRD的曲线轨道上任意位置处的动力响应。对安装TRD的曲线轨道动力特性进行计算分析可知:TRD能够显著降低曲线轨道在TRD自振频率附近频段内的振动响应并有效抑制曲线轨道的pinned‑pinned共振;安装TRD后,曲线轨道钢轨振动衰减率明显增大;TRD对不同半径曲线轨道的动力响应均具有一定的抑制作用;移动谐振荷载作用下,当荷载激振频率大于轨道自振频率时,安装TRD的曲线轨道时域振动响应被不同程度地抑制,当荷载激振频率与TRD自振频率一致时,轨道的振动响应显著降低。

A curved track-TRD analytical model is established in this paper.The TRD has two natural frequencies and the curved track is simulated by the discretely supported Timoshenko beam based on the theory of infinite-periodical structure.By using mode superposition method in frequency domain,the dynamic response of one point on the track can be obtained by calculating the track dynamic response at the corresponding point in a basic cell.After obtaining the dynamic response of the curved track-TRD model,some conclusions can be drawn.TRD is effective on controlling the track vibration in a broad frequency range and restraining the pinned-pinned resonance of the track.The rail decay rate increases after the TRD is installed.TRD can restrain the dynamic response of tracks with different radius.The dynamic response of the track under a moving harmonic load is reduced when the load frequency is higher than the first order natural frequency of the track.The vibration response of the track is significant reduced when the excitation frequency of the moving load is equal to the natural frequencies of the TRD or the frequency of the track pinnedpinned resonance.