Experimental Investigation Of Stress Distribution And Fatigue Behavior Of Steel Orthotropic Deck Plate

The orthotropic steel deck plate has been widely used in various steel bridges, especially in the steel box girder bridges. In this paper, based on domestic and foreign literature, the static and fatigue tests of full scale model of orthotropic steel deck plate were carried out in order to look in to the mechanism of the fatigue of the orthotropic deck plate, at the same time numerical analysis is in progress in which the shell and solid elements are used. By analyzing the test results and the numerical results, the stress distribution and fatigue properties of orthotropic steel deck plate were studied.In this paper, when the cases of static loading were simulated, the finite element model that adopt shell element was used. The distribution of transverse stress of the deck plate at the joint of deck plate, ribs and cross beam, principal stress at the cutout and vertical stress at the wall of ribs were studied. The results of test and numeric calculation matched well. The stresses were analyzed, when the loading locations of the same loading condition are different or when the loading locations of different loading conditions were the same. The maximum value of concerned points and the location of loading when the maximum value was reached were summarized. The effect of loading location and loading intensity were analyzed.In the process of fatigue test, the stresses were monitored and the fatigue cracks in steel deck plate were observed, and the stress cycles were noted at that time. When the stress cycles reaches 0.5,1,2,3,4,5,7,8,9,9.5 and 10 millions, the static tests were carried out. The fatigue test results showed that the fatigue strength of the cracking detail was correspond to the category C of AASHTO and the category 90 of EUROCODE.Finally, two part box girder models of a suspension bridge and a cable stayed bridge were created. In order to define the worst transverse loading location, the axel load acted on different transverse locations. Then, the fatigue truck moved along the lanes to obtain the stress course of concerned points. Based on the stress course, the stress range spectra was obtained by rainflow method. The fatigue evaluation of nanjin third bridge was conducted at last. The computing fatigue stress and fatigue life evaliaton results showed that the detail of rib-deck and rib-cross beam were sensitive to fatigue.