Test And Study Of Load Spectrum Of C70Universal Open Wagon Car Body

Open wagon C70is the main force of railway freight transport in China, so the service condition and the fatigue strength design condition matters a lot to railway freight transport in China, which means the reliable data and methods of fatigue assessment are necessary. Nowadays, China is short of reliable data for fatigue analysis of railway freight car, due to the lack of load spectrum which can represent the universal railway lines conditions in China. The load spectra that can represent the conditions of universal railway lines in China, on one hand, can be used to evaluate the fatigue strength of freight cars that are on active service and provide guidance to overhaul; on the other hand, can be used as data for fatigue design of new type freight cars. This thesis was based on the data from spectra test of open wagon C70, and the main research content in this thesis can be summarized as following aspects:(1) The experimental method of spectra test of railway freight car was studied. This thesis came up with a test method about how to install force transducers, strain gages and acceleration transducers on open wagon C70, which can be used in a harsh testing condition in a long distance and a long time.(2) The testing data was collected and processed. The testing data was collected from test on distance of11431KM. The spectra of C70on vertical, lengthways, torsional and rolling conditions were established, which could be crucial data for fatigue design of new type of railway freight cars in China.(3) The finite element model of C70was established. The fatigue focus parts on the car body were found through the finite element calculation under vertical, lengthways, torsional and rolling conditions. The load-stress transformation factor was got, which can transfer the load spectra into stress spectra.(4) The load spectrum damage and the stress spectrum damage were calculated, based on AAR standard and BS-EN standard. The correction factor of load spectrum damage was achieved through the comparison between load spectrum damage and stress spectrum damage, so that a method to evaluate the fatigue life of open wagon directly by load spectra was achieved.