京滬高鐵接觸網零部件疲勞試驗條件研究

侯日根

京滬高鐵接觸網零部件疲勞試驗條件研究

侯日根

接觸網零部件長期受各種隨機載荷的影響，容易發生低周疲勞。本文針對京滬高鐵接觸網零部件的現狀，利用弓網仿真建立某區間接觸網模型，分析吊弦、支持與定位裝置的工作載荷和位移分布，設計吊弦、支持與定位裝置的疲勞試驗條件，得出吊弦疲勞試驗的加載范圍、循環周期、幅值參數取值；支持與定位裝置疲勞試驗加載靜態載荷后，再對定位點加載位移載荷，得到幅值周期的取值范圍。

接觸網；吊弦；支持與定位；疲勞試驗

The OCS fittings are liable to generate the low cycle fatigue due to long-term suffering from various random loads,with regards to current conditions of OCS fittings for Beijing-Shanghai high speed railway,by establishment of OCS model for pantograph-catenary simulation,analyzing the work loads and offset distribution of droppers,supporting and registration devices,defining the fatigue test conditions for droppers,supporting and registration devices,the taking values for scope of loading,cycle period and amplitude parameters for the fatigue test of droppers are obtained.The scope of taking values for amplitude cycle are obtained on the basis of static loads being applied on the supporting and registration devices and offset loads being applied on the registration point.

OCS;dropper;supporting and registration;fatigue test

0 引言

接觸網零部件受接觸網內部和外部載荷的影響，如補償裝置、溫度引起線索張力變化屬于接觸網內部載荷變化；受電弓帶來的載荷、風載荷屬于接觸網外部載荷。內部載荷改變接觸懸掛的線索張力是逐步的、漸進的，但是接觸網外部載荷如受電弓帶來的載荷，屬于沖擊性載荷，其特點是當受電弓通過某區段接觸網時，引起接觸網零部件的內部應力大幅變化，受電弓通過后，內部應力重新分布，接觸網零部件恢復到其原有靜態平衡位置。風由于具有脈動性，時有時無，屬于沖擊性載荷，對接觸網零部件的影響也不容忽視。

接觸網零部件隨時受內部靜載荷（假設溫度變化緩慢）的影響，一旦外部載荷如受電弓沖擊性載荷與之相互作用，引起零部件內部應力變化劇烈，當零部件長期受到幅值變化的交變應力作用，會引起接觸網零部件的周期性疲勞，若交變應力幅值較大，可能引起低周疲勞，交變應力幅值較小，可能引起高周疲勞。……