| The anchorage zones of cable-stayed bridges, which bear giant cable forces and have complicated structure, are key parts to the bridge. It is important to know the stress distribution of anchorage zones well. This thesis mainly focuses on load transferring mechanism and the ultimate strength of the cable-pylon anchorage zone, under staying cable forces, based on Changshou Chongqing Yangtse River Highway Bridge under construction.Firstly, by determining the stress loss of the great tonnage small radius prestressed steel ties, the paper provides the passageway frictional coefficientsμand k value of the plastic corrugated pipe, also gives guidance suggestions on prestressed technique. Then, with the use of large-sacle finite element analysis software ANSYS, simulating calculation of the anchorage zone in actual work condition is done. So the spacial stress distribution is obtained. According to the space stress analysis, a full-scale pylon segment model including one whole anchorage of cable is tested, with the the same support condition as the actual structure. By contrasting the actual value of prototype experiment and the theoretical value of finite element analysis, we found that the stress’ distribution regularity of the two were basically identical, and this proved that the calculation method was correct. This experiment took follow-up observation on cracks of concrete surfaces, drew cracks’ distribution pictures and analyzed how cracks formed. According to the experiment’s results, the structure performed elastic behavior under two times designed cable forces, and the safety factor are bigger than 2, which showed that the structural design can be regarded to be safe and reliable. This experiment observed stresses which were relatively heavier in the anchorage zone, and the data tend to be safe. All the results deduced by this paper are valuable and can provides references to the design, construction, monitor and control of the cable tower anchorage zone of cable-stayed bridge. |
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