车速对钢轨接触疲劳伤损的影响及高速线路钢轨选用

Influence of Train Velocity on Rail Contact Fatigue Damage and How to Select Rail for High-speed

采用专门的试验机对不同线路条件钢轨的接触疲劳伤损特点进行模拟试验研究。结果表明,车速在200 km/h以下时,随车速提高钢轨的磨损量减小、接触疲劳伤损加剧;车速达300km/h时,钢轨的磨损量和接触疲劳伤损均减轻。该试验结果得到了计算机仿真计算结果相符。通过对试验结果的分析,认为车速在200km/h以下的客货共运快速线路,宜选用强度为1100MPa级的热处理钢轨;车速达300km/h左右的高速客运专线,应考虑选用强度较低、但裂纹萌生和扩展速率较低、K(?)值相对较高的U71Mn热轧钢轨,或成分性能与之相类似的其它钢轨。

The simulation tests of rail contact fatigue damage in varied railways were carried out at a professional test machine. The results show the rail wear decreases meanwhile the contact fatigue damage increases with the train velocity increase when the velocity is below 200 km/h, and both of them decrease when the train velocity reaches 300 km/h. The results accord with the numerical simulation on computer. So it is concluded that the heat treated rail whose tensile strength is 1 100 MPa should be selected when the train velocity is below 200 kin/h, and U71Mn hot rolled rail whose tensile strength, crack birth rate, and crack extension rate are relative low, or other rail whose component and property are similar to the U71Mn hot rolled rail, should be selected when the train velocity approaches 300 km/h on the only passengers transport railway.