Study Of Load Characteristics Of C70 Car-body Based On The Line Tracking Test

In 2013, China carried out railway wagon C70 type gondola car general line load spectrum test in three railway line from Beijing to Chengdu, Beijing to Harbin and Beijing to Guangzhou. The total mileage is 26000 kilometers, covering a variety of marshalling circumstances and line conditions. The test line is representative of the general line. Therefore, the results of load characteristics of C70 car-body can be extended to the whole railway line and could lay the formation of fatigue design standard and test evaluation standard of railway freight cars in our country. Based on this test, load characteristics of sink-float load, side-roll load, torsion load and longitudinal load of car body were analyzed. Main research contents are as follows:1. Study the method of obtaining the four major load of car-body. The load time-history of the central plate and side bearing is observed and analyzed when the car body is in sink-float motion, nodding motion, side-roll motion and torsional motion. The coupler longitudinal load variation characteristics are analyzed during the starting, braking and shunting operation of train.2. Summary tests and divide the marshalling circumstances into three cases by the position of the test car. The test car is at the top 1/3, middle 1/3, or last 1/3 of the train. Do normalization processing for different marshalling circumstances. Build the car body load spectrum of different railway lines, different marshalling circumstances and shunting work conditions.3. The critical load characteristics of the car body under different line conditions are compared and analyzed from the load time-history, the extreme load value, the cumulative frequency per kilometer. The influence of different formation conditions on the extreme load value is evaluated by the method of large value accounting and graph fitting. Use the value of the load spectrum calculated by the method of equivalent load to compare the critical load spectrum of the car body.4. The distribution of the car body load data is obtained under the full operating condition and the maximum value of four kinds of car body load is obtained under the large data. Select representative formation conditions. Use statistical inference to deduce the maximum value of sink-float load and longitudinal load of car body under extremely low probability. Connect longitudinal load data under shunting connection state and deduce the maximum value.The statistical inference results are analyzed.