Reinforcement Mechanism And Application Of External Prestressed Concrete

The maintenance and reinforce treatments of engineering are problems to which people have paid close attention at all times. So far a lot of achievements have been taken out in reinforce measures. But there are many problems still waiting solved. As the important part of post-tensioned concrete structure system, external pre-stressed is a kind of pre-stressed concrete structure system that bring pre-stress to steel cable which is lie out of main span of load-carring member. Using external pre-stressed may predigest the curve of pre-stressed reinforcement, decrease friction loss, lighten own weight of structure;may exchange pre-stressed reinforcement, and easy to be examined and serviced;and the construction technique is simple . So, external pre-stressed is widely used in the field of reinforce engineering .especially in the reinforcement of bridge.Through theoretical analysis and numerical simulation methods, the increment of stress calculation reinforcement mechanism reinforcement design and its evaluation to the concrete beam with external pre-stressed is studied at large. It has great theoretical meaning and application value, also can offer references to reinforcement treatment, and is easy to carry through more reasonable design , and improve the capability of structure, the mostly work are follow:Firstly, improved calculation method is studied against the limitation in the design and calculation to the method of the increment calculation of external prestressed, that is strain energy method. The result of this method is according with the force method, but this method is more simple and can adopt numerical calculation then can be extend to more complex structure, and then the method is commonly. Consider from the compute process of those two method, strain energy method is more simple and convenient.Secondly, from the two phase of bring prestressed and liveload, through analyse the reciprocity relation of external pre-stressed cable and beam, reinforcement mechanism of external pre-stressed cable be studied by using equivalent load theory. And the secondary bending moment of continuous beam be calculated by adopting equivalent load method.Finally, from the view of numerical simulation , using ANSYS which is one kind of FEM software, the mechanism of action of external pre-stressed cable is discussed by the analysis of stress strain deflection and so on which is fore-and-after of concrete simply supported beam of external prestressed of reinforcement;and analyse the reinforcement effect of external prestressed reinforcement according to reinforce a continuous rigid frame bridge.