| Under the background of Shanghai Yangtze-River Bridge which is a light-railway and highway cable-stayed bridge, fatigue behavior of a full scale test of steel box anchorage was studied in this thesis. Because of the greater live load range due to train load, it was important to study the fatigue behavior of cable-girder anchorage.With the global analysis of FEM, the segment of the maximum cable force range induced by design live loads was selected for FEM segmental model, whichi was used to analyze the transition of cable force and stress distribution in box anchorage. Based on the static FEM analysis results, the full scale test model was designed by the major rule of similar stress simulation in key regions between the local segmental model and the fatigue test model. The correctness and applicability of test model were identified by the comparison of the FEM analysis results of these two different models.For the convenience of fatigue test, both two cable forces due to vehicle and train load were transformed to an equivalent force of 2,000,000 cycles by Palmgren-Miner rule. Referring to BS5400's Code Part 10, the equivalent force of 2,000,000 cycles is 2030kN and the fatigue test load range was set to 200kN～ 2230kN. The fatigue test results showed that, the fatigue behavior of such type of anchorage was quite good. There were no cracks found in test model after 2,000,0000 cycles of a test load range 2030 kN and 1,000,000 cycles of a test load range 2420 kN.In the last part of the thesis, evaluation of fatigue strength and life in the positions of checking computations in the weldings of bearing load in box-shaped anchorage was made by referring to AASHTCK BS5400, Eurocode. The evaluation showed that, the anticipated fatigue life calculated by referring to Eurocode was more conservative and a bit little than the minimum design fatiue life. The method of fatigue evalution based on Eurocode could be used for preliminary fatigue design.
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