路面随机激励下长管拖车框架疲劳分析

通过框架式长管拖车框架的有限元模态求解,获得了框架的固有频率。采用模态叠加法计算了路面随机激励下框架的应力响应,分析掌握了框架的动态特性,并根据求解结果对框架进行了随机疲劳强度计算。研究结果表明,在紧急刹车工况时框架受到的惯性力最大,应在行驶中尽量避免紧急刹车情况;框架在A、B级路面可以满足疲劳损伤要求,并可以进行结构轻量化改进以减小车体质量,在C、D级路面不能满足疲劳损伤要求,应进行抗疲劳设计。

Fatigue Analysis on the Frame of Long Tube Trailer under Random Vibration

By establishing the finite element model on the frame of long tube trailer, the modal analysis was carried out and the frame natural frequency was obtained. The stress of the frame under random excitation was calculated by the modal superposition method and the dynamic characteristics of the frame were analyzed. The random fatigue strength of the frame was calculated according to the calculation results. The results show that the inertia force of the frame is the largest under the emergency braking condition. Emergency braking should be avoided during driving. The frame can meet the fatigue damage requirement and be improved in structure to reduce the body mass on the class A and B pavement however the fatigue damage requirement can not be satisfied on the class C and D pavement and the fatigue resistance design should be carried out.