地铁弹性短轨枕轨道的钢轨波磨萌生原因

为探明我国某地铁线路弹性短轨枕轨道曲线钢轨短波长波磨萌生原因，采用现场试验和数值仿真方法对其开展了研究. 首先，通过现场试验确定钢轨波磨波长与轨道动态特性对应关系；其次，利用车辆-轨道耦合动力学模型计算轮轨接触参量，通过力锤敲击法获得现场轨道导纳特性；最后，基于轮轨接触参量和轨道导纳结果，建立钢轨波磨频域线性分析的数值模型，模拟弹性短轨枕轨道频域下曲线钢轨磨损率特征，分析了弹性短轨枕轨道萌生特定波长波磨原因. 研究结果表明:地铁弹性短轨枕轨道钢轨波磨主要出现在半径小于等于800 m曲线段，低轨波磨程度更为显著，波长为50～160 mm，通过频率为140～280 Hz；轨道在160～210 Hz频率范围的模态振型表现为钢轨和轨枕一起相对轨道板垂向弯曲振动，在250～300 Hz频率范围的表现为钢轨和轨枕垂向反向振动，波磨通过频率与该轨道的160～300 Hz共振频率相近. 弹性短轨枕轨道特定波长波磨萌生主要与其轨道垂向固有特性相关，其波磨特征为频率固定型，波磨波长随车辆运行速度变化而变化. 

Initiation Cause of Subway Rail Corrugation on Track with Rubber-Booted Short Sleepers

To investigate initiation cause of short-pitch rail corrugations occurred on curved tracks with rubber-booted short sleepers, field measurement and numerical simulation methods were employed. Firstly, establishment of the relationship for wavelength of the rail corrugation and dynamic behaviour of the track was facilitated by the field measurement. Then, wheel-rail contact parameters were calculated by a vehicle-track coupled dynamics model. Receptance of the tracks was measured by an impact excitation technique. At last, a linear model for the rail corrugation was established to analyze characteristic of rail wear based on the wheel-rail contact parameters and the receptance of the tracks. Rail wear rate of the tracks in the frequency domain was calculated during a vehicle running at curves. The initiation cause for rail corrugations with specific wavelengths occurred on the tracks with rubber-booted short sleepers was clarified. The results show that corrugations for the tracks with rubber-booted short sleepers have occurred at curves with radius of less than or equal to 800 m. Main wavelength of the corrugations is about 50?160 mm and level of the corrugations on low rails is higher than that on high rails. Passing frequency of the corrugations is in the range of 140?280 Hz, which is close to resonant frequencies (160?300 Hz) of the track with rail vibrating related to sleepers. Modal shape of the tracks exhibits rails and sleepers vertical vibrating on the slab in same and opposite directions at frequencies of 160?210, 250?300 Hz. Initiation of corrugation on the curved tracks is determined by the dynamic behavior of the tracks. Characteristic of corrugations exhibits the fixed-frequency mechanism, which means wavelength of the corrugations is related to the speed of vehicle.