Study On Fatigue Property Of Ear-plate Cable And Beam Anchorage Of Highway And Light-railway Cable-stayed Bridge

The cable and beam anchorage of highway and light-railway cable-stayed bridge has acomplex structure and the stress is in concentration. The fatigue problems of the cable anchoragezone of the highway and light-railway cable-stayed bridge are even more prominent than thehighway cable-stayed bridge. Based on fatigue strength theory and fatigue damage cumulativetheory, with Hongyancun Jialing-River Bridge as actual project, the paper starts with the study onfatigue load, and then studies the fatigue property of ear-plate cable and beam anchorage ofHongyancun Jialing-River bridge via the finite element technology. The content is as follows:1. Sorting and analyzing the domestic and foreign researches on the cable and beamanchorage, the paper analyzes the fatigue load models and the fatigue assessment methods of thedomestic and foreign specifications.2. Establish the numerical model of Hongyancun Jialing-River Bridge by the finite elementsoftware MIDAS, the cable force under live load is calculated, and determines the ear-plate cableand beam anchorage on the beach side as the research object.3. The fatigue load amplitude of the cable and beam anchorage is determined respectively bythe random traffic simulation, standard fatigue car of Miner theory and fatigue models of thespecifications. Through the comparison, the paper find that the method of determine the fatigueload by calculating the equivalent standard fatigue car based on Miner theory is simple and theresult is relatively accurate.4. Using ANSYS, thefinite element analysis software, establish the finite element model ofthe ear-plate cable and beam anchorage, the mechanical characteristics, force transmission and thecable distribution of the plates of the steel anchor box are determined by calculation.5. By emulation analyzing the process of the fatigue load put on the the ear-plate cable andbeam anchorage, the fatigue property is studied. Then find that the max stress on the ear-platecable and beam anchorage is220.61MPa, which means it do not reach the the material allowablestress. The change of stress of control points is linear, and the stress condition of the maincomponents and near the main welds isn’t abnormal.6. Using the Fatigue loads which are respectively determined by the equivalent fatigue standard car model, design code of highway steel bridge (JTG D64-201x approval draft), BS5400,AASHTO and Eurocode, the checking calculations of the ear-plate cable and beam anchorage arerespectively carried out based on the regulations of the specifications. Find that the max amplitudeof the positive stress is51.0MPa, the max amplitude of the shear stress is15.2MPa, which meansthat the results satisfied the requirement of the specifications. Thus, the fatigue reliability of theear-plate cable and beam anchorage of Hongyancun Jialing-River Bridge is verified theoretically.