Study Of Fatigue Performance And Experiment Schemes Design On The Bonding Part Which Is Formed Between The Cross Beam And The Side Wall Of High-Speed Railway Space Rigid Frame Bridges

Steel-concrete composite structure has been used more and more widely in bridge engineering, and provides a broader space for bridge construction in recent years. However, it is difficult to master working mechanism of such composite structure as its complex materials and constructional details, and the longer it is used, the problem of fatigue is more obvious and serious. As a result, it is important to study the fatigue performance of steel concrete composite structure.Based on the fatigue test of transverse beam and side wall composite segment for the space frame bridge on Beijing-shanghai express railway, the paper discusses the loads of fatigue test, analyzes the experiment model by finite element method and designed the fatigue loading testFirstly, this paper briefly introduced development history of steel-concrete composite structure as well as present research state of its fatigue problem at home and abroad. The paper also introduces some basic conceptions about fatigue strength, including the fatigue damage cumulative theory and fatigue life curve etc, and analyzes the main factors affecting the fatigue strength of steel-concrete structure.Secondly, the paper places the emphasis on studying the internal force amplitude as the question of how to determine the amplitude is the key to fatigue research. According to the relative documentation at home and abroad and the actual engineering background, the paper calculates the internal force amplitude by two different calculation thoughts, then compares results between two methods and points out their advantage and shortcoming, and chose the more unfavorable result as reference value in order to ensure the security of structure.In the end, the paper chose the test position combined with the actual engineering background, and designs the loading model of fatigue test with reference to design methods and ideas at previous tests. The paper finally draws up the test loading scheme according to the stress distribution of model through calculating and analyzing the test model by finite element software...