Stress Analysis And Full-scale Model Test Study To Anchorage Zone Of Pylon Of Three Tower Cable-stayed Bridge

The anchorage zone of the pylon is a key part for cable-stayed bridges, where the local concentrated force of cable will be transferred to the pylon safely and uniformly. Because of the powerful local concentrated forces, anchoring forces from prestressed steels and weaken factors from opening holes, the strength state at this area is very complicated. Therefore, analysis of strength performance at the anchorage zone of cable-stayed bridge tower has been attracted attention in bridge engineering all the time and anchorage zone of tower is also the difficult and important part in designing and constructing of cable-stayed bridge. The Binzhou Yellow River highway bridge is on our country Yellow River the first three tower diagonal cable-stayed bridge, to three tower diagonal cable-stayed bridge, the experimental study which having been carried on is very few, relativing to double tower or the single tower diagonal cable bridge, the structure is more complex and the influence factors are more. In view of this present situation, for the consummation correlation theories analysis and the experimental study, especially the highest position to three tower diagonal cable bridges, the biggest self-possessed, the biggest horizontal force slanting back guy correspondence anchorage zone of pylon carries on the stress analysis and the test of full-scale model,to examine the stress performance of the anchorage zone of pylon, and for the construction craft proposed the guidance suggested, simultaneously is rich and the perfect correlation theories analysis and the experimental study. First,we carried on the spatial stress finite element analysis using the ANSYS software in view of the rope tower anchor area N26 stage; Then, we carried on the test of full-scale model to anchorage zone of pylon, the test condition is completely same to the actual construction craft.Through determining the stress loss which the great tonnage small radius prestressed steel ties, giving the plastic corrugated pipe the passageway frictional coefficient μ and the k value, contrasting analysis prototype experiment actual value and the finite element analysis theoretical value,determining concrete temperature curve, and carringon the discussion to the prestressed passageway vacuum assistance assistant pumping technique also. According to the space stress analysis and the test result of full-scale model, in the aspects of the ring prestress, the vacuum assistance pumping technique and concrete construction quality controlling, the guidance proposal and the request were put forward to to the project entity construction control. Through the finite element analysis and the full-scale model test, finally drawing the results: The finite element space analysis and the test actual result of full-scale model tally basically; The model anti-crack safety coefficient and the crack opening safety coefficient are bigger than 2, the structural design is safely reliable,the spatial analysis result had also indicated this point; The vacuum assistance pumping technique is scientific, it can guarantee the passageway in the milk the uniformity, forms dense protector, provides the effective protection to in the pipeline pre-stressed muscle; The model concrete mixture ratio conforms to the intensity target requirement which the design proposed, and has the enough safety margin.