Experimental Study on Dynamic Properties of a Recycled Composite Sleeper and Its Theoretical Model

再生复合材料轨枕动力特性及其理论模型的实验研究

As a symmetrical structure in track system, the dynamic properties of recycled composite sleepers are important factors affecting the vibration characteristics of track structure. To study the viscoelastic dynamic properties of the composite sleeper, dynamic mechanical analysis (DMA) tests of a composite sleeper at −5 to 30 °C and 1–60 Hz were first carried out, and then the time-temperature superposition (TTS) and the Williams–Landel–Ferry (WLF) formula were used to predict the dynamic properties of a composite sleeper at a wider frequency range. Finally, the generalized Maxwell model was adopted to characterize the dynamic properties of the composite sleeper, which provides parameters and theoretical models for dynamic analysis. The research results show that the composite sleeper has obvious viscoelasticity. Its modulus is large at low temperature or high frequency. On the contrary, the modulus is small at high temperature or low frequency. Under the test conditions, its complex modulus ranges from 1500 to 2700 MPa. The loss factor is in the range of 0.08–0.13. Using the generalized Maxwell model (n = 4), which can better reflect the dynamic properties of the composite sleeper.

作为轨道系统中的对称结构，再生复合轨枕的动力特性是影响轨道结构振动特性的重要因素。为了研究复合轨枕的粘弹性动力学特性，首先对复合轨枕在-5至30°C和1-60 Hz下进行了动态力学分析（DMA）测试，然后运用时温叠加（TTS）和Williams–Landel–Ferry（WLF）公式预测了复合轨枕在较宽频率范围内的动态特性。最后，采用广义麦克斯韦模型表征复合材料轨枕的动力学特性，为动力学分析提供参数和理论模型。研究结果表明，复合轨枕具有明显的粘弹性。在低温或高频下其模量大。相反，在高温或低频下模量较小。在测试条件下，其复数模量变化范围为1500至2700 MPa。损耗因子在0.08–0.13的范围内。使用广义麦克斯韦模型（n = 4），可以更好地反映复合轨枕的动力特性。

Zhao Z, Gao Y, Li C. Experimental Study on Dynamic Properties of a Recycled Composite Sleeper and Its Theoretical Model. Symmetry. 2021; 13(1):17. https://doi.org/10.3390/sym13010017