Vibration On The Vehicle Structure Typical Of The Dynamic Stress

With the railway freight transportation developing to the heavy load, China has opened the line of the Datong-Qinhuangdao which is 2 million tons overload. The gondola car of C80B type designed for the line, whose steel car body appearances the premature breakage problems during the working. The fatigue cracking phenomenon of the body's key parts is increasing significantly, such as:the inside of the body's pillow-beam, the top surface of body center plate, the top surface of the medial-beam,the intersection of the side-beam and the side-wall and the intersection of other key parts, the main reason of the fatigue damage is the vibration during vehicle operation. Most of the vehicle energy is concentrated in low frequency vibration, which is the typical complex vibration combined by the body's floating and sinking, rolling pendulum, nodding, shaking its head and basic types. So it is necessary to consider the impact of the stress during the operation of dynamic the typical vehicle vibration worked on the body.From the situation of the current study, most of the vehicle's vertical force research stays in the simple level of static analysis, considering the impact of the stress during the operation of dynamic the typical vehicle vibration worked on the of the body rarely. Actually the vehicle operated by the track irregularity major incentive, which is main reason for the variety vibration of vehicles. Vertical track irregularity can cause the vehicle vibration and rolling pendulum vibration nod, and would lead the wheel weight fluctuations, which is not only increasing the wheel-rail vertical force and vertical acceleration of the body, but also affecting the stability of the line, reducing the running smooth and security. The article is inspired from the vertical vibration caused by the typical start, using the structural dynamics and finite element analysis techniques, establishing the C80B Gondola Car's finite element model treating the track's vertical irregularity as the dynamic boundary condition, to simulate the vehicle's typical vibration under different excitation frequency tracks, and thus to calculate action-responding, and obtain the displacement-time history,dynamic stress-time history,acceleration-time history of the key parts of the body. Analyze the dynamic stress distribution of vehicle body vibration process of and the location of key points, and compare with the static stress; and then according to the corresponding relationship between wavelength and frequency, by changing the wavelength of the excitation to design different frequency's irregularity, to further explore the influence of the orbital excitation frequency on the structure dynamic stress and the center acceleration of the body.