Fatigue analysis of large-span steel structure induced by high speed train

The special passenger railway from Wuhan to Guangzhou is the longest special passenger railway in China, and also with the features of the highest technical standards and the largest investment scales. The station adopted the structural form of combination of bridge and building, which is difficult to analyze its dynamic behavior and structural stability. Numerical calculation model for moving loads and bridge is established by the software ANSYS based on the basic theory of dynamic response of simple supported beam under moving loads, in which the high speed train was modeled by a series of moving loads. The time history and Fourier spectrum of reaction at bearings are obtained. And dynamic response of upper large-span grid structure is calculated under the above reaction. The stress state of the large-span grid structure, vibration mode and its weak parts are determined. Stresses time history at the weak parts are extracted and load spectrums are obtained by rain-flow counting method. The fatigue life of the upper large-span grid structure under high-speed train load is calculated, which shows that the structures is safe in its design service life.