Prestressed System Analysis Of The Cable Tower Anchorage Zone Of Cable-stayed Bridge

In recent years, with the development of the economy in China, bridge construction are developing quickly。A large number of super-long span cable-stayed bridges appeared in our country.,because of the increment of span,in the design of pylon of super-long span cable-stayed bridge,the designed tonnage of cables achieves "kiloton"grade.And then the stress in the anchorage zone of pylon becomes greater and greater,how to ensure the crack resistance and the ultimate bearing capacity of concrete in the anchorage zone of pylon become an important subject.Shaying River Bridge in Zhoukou city is taken as an ergineering example,this paper make the following research about the prestressed system in the anchorage zone of pylon.1.In order to withstand the tremendous cable force ensure the crack resistance and the ultimate bearing capacity of concrete in the anchorage zone of pylons,usually set the level prestressed reinforcement in pylon.On the Shaying River Bridge井-type prestressed system is used in pylon. This system has such advantages:stressing definite, simple construction, but under the existing code to calculate the lossing of the prestressed is not accurate. Articles simulating on-site construction of the situation, make a experimental research on the prestress loss about anchorage zone, by mathematical statistics method, obtained the relationships between torque anchor size and the prestress loss through the process of applied torque in anchorage zone.Experimental simulation process, can guide the construction of this bridge, but also to promote the exchange as a result.2.Because of the powerful local concentrated forces,anchoring forces from prestressedsteels and weaken factors from opening holes,the strength state at this area is very complicated. There are no existing codes can be used to apply the calculation of this zone,so analysis of strength performance at the anchorage zone,not only used the model test but also used the finite element method. Learn from experience in previous studies,by finite element software ANSYS this pape select a standard segment of the cable-stayed bridge,analyzing in the different conditions, the concrete is stress state in the anchorage zone of pylon, obtained the rationality foundation of prestressed system in this zone.The laws in this paper can be used desige and construction of anchorage zone of pylon for this bridge,and is useful for directing research and analysis of such anchorage zone of pylon.