| The orthotropic steel bridge decks are widely used in long-span bridges at home and abroad.Fatigue problems are the key issues affecting durability.The main damage form of the orthotropic steel bridge decks e is fatigue failure,so it is very important to anti-fatigue design is reasonable,however,the premise of anti-fatigue design is to obtain the fatigue stress spectrum that accords with the actual operation conditions.At present,the fatigue stress spectrum for calculating the fatigue structure details does not consider the influence of the lateral distribution probability of the wheel track,resulting in a difference between the calculated stress spectrum and the true stress spectrum.Steel bridge deck will bear the role of vehicle wheel load directly during the service period of the bridge,and the frequency of action is extremely high,so the steel bridge deck is prone to fatigue cracks.In this paper,the actual lateral distribution of wheel traces of a domestic road vehicle is measured,and the lateral distribution probability of the vehicle wheel track is given.Under the premise of considering the lateral distribution of the wheel load,a fracture mechanics method that can consider the influence of initial cracks is used to analyze the orthogonality.The stress intensity factors of fatigue cracks in the fatigue structural details of anisotropic steel bridge deck are analyzed with different variations of crack propagation and lateral loading.The effect of vehicle wheel load lateral distribution on fatigue residual life is analyzed.The main contents are as follows:1.Summarize the application of orthotropic steel bridge deck at home and abroad,briefly explain its fatigue problems,causes,and research status,and focus on summarizing fatigue problems in the application of orthotropic steel deck in China.2.Summarizes the study of horizontal distribution of vehicle wheel traces at home and abroad.The horizontal distribution of wheel traces of a domestic road vehicle is actually measured.The frequency distribution of the horizontal position of the vehicle wheel traces is statistically analyzed and compared with the distribution probability of foreign vehicles.3.According to the typical structural details of the steel deck panel,the finite element model of the steel deck panel was built,and the fatigue loading was carried out in different lateral positions of the lane.The stress history of certain structural details under different lateral position loading was obtained.The cumulative damage theory was based on miner.The impact of standard fatigue on the fatigue performance of various structural details of orthotropic steel deck panels was evaluated,and the sensitive structural details were summarized.4.Set up the crack model of different structural details of orthotropic steel bridge decks,calculate the stress intensity factors of cracks under different lateral distribution of vehicle wheel traces and crack lengths,analyze the variation law,and then solve the steel bridge.The fatigue remaining life of the panel's sensitive construction details is analyzed. |
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