铁道建筑

针对轮轨高频激励引发的单趾弹簧扣件弹条共振断裂病害，设计了适用于单趾弹簧扣件的新型高频无螺栓弹条。设计扣压力为6.5～7.5 kN，设计弹程12 mm，弹条安装后固有频率不低于800 Hz。建立仿真模型，对新型弹条进行静态、动态力学性能检算及模态计算；对新型弹条试件进行扣压力试验、弹条疲劳及残余变形试验、固有频率试验，并在存在轮轨高频激励的地段进行现场铺设。结果表明：经仿真计算，其静态最大应力为1 329 MPa，小于材料屈服强度；每毫米变形应力为110.7 MPa，与国内常见无螺栓弹条基本相当；卸载、加载应力均小于弹条抗拉强度；第1阶固有频率为1 057 Hz，满足设计要求。其扣压力、疲劳后残余变形均满足设计和规范要求，经500万次标准疲劳试验和大振幅疲劳试验后均未发生断裂。标准组装状态下实测弹条固有频率平均值为982 Hz。现场铺设10个月内未发生断裂现象。对于存在轮轨高频激励的地段，新型高频无螺栓弹条有更大的安全储备。

In response to the resonance fracture disease of single toe spring fasteners caused by high-frequency excitation of the wheel rail, a new high-frequency boltless clip suitable for single toe spring fasteners was designed. The designed clamping force is 6.5～7.5 kN, the designed stroke is 12 mm, and the natural frequency of the clip after installation is not less than 800 Hz. A simulation model was established to perform static and dynamic mechanical performance checks and modal calculations on the new type of clip, the clamping pressure test, fatigue and residual deformation test, and natural frequency test were conducted on the new type of clip specimens, and the on-site laying application was implemented in the section with the high-frequency excitation between the wheel and rail. The results indicate that through simulation calculations, the maximum static stress is 1 329 MPa, which is less than the material yield strength. The deformation stress per millimeter is 110.7 MPa, which is basically equivalent to the commonly used boltless clips in China. Unloading and loading stress are both less than the tensile strength of the clips. The first natural frequency is 1 057 Hz, which meets the design requirements. The clamping force and residual deformation after fatigue could meet the design values and specification requirements, and no fracture occurred after 5 million standard fatigue tests and large amplitude fatigue tests. The average natural frequency of the testing clips in the standard assembly state is 982 Hz. No fracture occurred during the 10 months of on-site installation and application. The new high-frequency boltless clip has a greater safety reserve than the original single toe spring fastener clip.