车辆焊接结构疲劳寿命评估方法研究

为在设计阶段实现车辆焊接结构的抗疲劳设计,在研究AAR/BS/IIW标准的疲劳算法原理和焊接接头疲劳性能参数的基础上,给出基于AAR/BS/IIW标准进行车辆焊接结构疲劳寿命评估的方法和技术路线。依据AAR标准分析某公司出口的全钢焊接结构矿石车车体的疲劳寿命,结果表明:该出口矿石车车体焊接结构的最短疲劳寿命发生在中部横梁腹板与横梁下盖板角接焊接区,寿命年限为59.4年,满足25年设计寿命的要求;通过与IIW标准中提供的焊接接头结构的对比分析,提出对某提速客车转向架焊接构架的定位座根部焊接结构进行打磨的改进方案。数据表明:改进方案明显提高了定位座根部焊接接头的寿命。经对比分析可以看出,基于IIW标准的焊接构架疲劳寿命预测结果与疲劳试验结果比较接近。

Study on the Analysis Method for Fatigue Life Prediction of Vehicle Welded Structure

To achieve fatigue life prediction of vehicle welded structure during design phase,practical analysis methods are presented by means of fatigue analysis principle and fatigue performance parameter of welded structure of AAR / BS / IIW standard.Fatigue life prediction results of an exported wagon by AAR standard show that the welded region located in middle of the wagon,where web and bottom of transverse beam intersected,has the shortest life-span(59.4 years) and satisfies the design requirement(25 years).Based on welded joints S-N curves provided by IIW standard and dynamic stress spectrum tested on line,fatigue life prediction for welded frame of speed-up bogie is given.Depending on the analysis results,an improved frame structure is presented.The frame analysis result is close to the test result.