VIBRATION ANALYSIS OF SIMPLE SUPPORTED BOX BEAM INDUCED BY HIGH SPEED TRAIN

摘要

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 standard and the largest investment scale. The Wuhan railway station adopts new structural form of the combination of bridge and building. As to the special structural form, the mass of upper steel structure passes to pier through V-shape supportings and vibration caused by high speed train will transfer to upper steel structures directly. The fatigue life of upper large-span steel structures under long-term reciprocating dynamic loads needs more attention. Numerical calculation model for moving loads and bridge is established by the software ANSYS based on the fundamental theory of dynamic response of simple supported beam under moving loads, in which the high speed train is modeled by a series of moving loads. The frequency and deformation and acceleration of beam are calculated. The time history and Fourier spectrum of bearing reaction are obtained. It is showed from calculation results that resonance will not be occurred and the technical indexes such as frequency and deformation and acceleration of the beam all satisfy the relevant technical regulations, which indicates that the dynamic design of the beam is rational. The calculation results in the paper provide foundations to analyze fatigue life of upper large-span steel structures.