Experiment Research On The Static And Fatigue Behavior Of Cable-Grider Anchorage Of Hei Xia Zi Island Wusu Bridge

The cable-girder anchorage zone of cable-stayed bridge bears huge cable forces and has complicated structure, which is the key to the structure design. It is important to research the static and fatigue performance of the anchorage structure.This thesis makes deep research into the static and fatigue performance of the cable-girder anchorage of WuSu bridge of HeiXiaZi island. The stress distribution, carrying capacity, and fatigue performance of the anchor box were investigated by using the theoretical and experimental methods.The main contents and conclusions are shown as follows:1. The common cable-girder anchorage of cable-stayed bridge in domestic and foreign were introduced, the structural characteristics and mechanical properties were analyzed. An anchoring structure test model of WuSu bridge of HeiXiaZi island was designed according to the experiences of the analysis on cable-girder anchorage research in recent years.2. The stress distribution of cable-girder anchorage was researched through the theoretical analysis and tests, according to the measured data of the structure, all equivalent stress of measuring points did not exceed the yield strength of the material, when the structure was under the1.0times and1.7times the maximum cable force. With the increased level of the load, each measuring point equivalent stress changed linearly. The measured anchor box stress distribution is the same as the theoretical calculation results. The cable-girder anchorage has well property and adequate safety reserve. The anchor box web parameter optimization studies have shown that, the stress concentration of the anchor box structure can be reduced a certain degree with enhanced anchor box web bending performance, and have a certain role to reduce the overall stress level of the anchor box.3. After2million fatigue cyclic loading, no damage occur with the test model. And after nondestructive testing, the main welds were well. The theoretical analysis and fatigue test results show that the stress of the anchor structure is much less than fatigue allowable stress under the fatigue loading. The test show that the fatigue performance of the anchorage structure meet the regulatory requirement, and has a sufficient safety margin.