External Prestressed Continuous Rigid Frame Bridge

In the method of the strengthenment of existing fault bridges formed in rencent years,the method of external presttessing have particular advantadge in enhancing the bearing capacity of the bridge. On the other hand, many using continuous rigid frame briges represent the phenomenons of the shortage in the bearing capacity. So,it seemed to be very important to research the applications of external presttessing in strenthening the existing fault bridges . In this paper,it is based on the method of external presttessing of continuous rigid frame brige,and by three method of diseas analysing, frame computing, construction supervision and measure to analyse and value the method of the strengthenment of external presttessing.At first,it analysed the characteristic and the theory of pressing the system of external presttessing,provided the formula in intensity of correctitude section,discussed the compute method of ultimate bearing capacity of the external presttessing reinforcing steel bar.Secondly, this paper based on the highway bridge of huanghe in sanmenxia, it educed the method of controlling by flexibility and stress through analysing the reason of some bridge disease. Through all of above ,it set up the model of scathe,so it can be right to analyse the reinforce bearing external presttessing. At the same time,it designed the project of construction supervision and measure aimed at the strengthening bridge by external presttessing,through the contrast between the result in theory and fact,we can see that it is feasible to use predigestion's computing based on elasticity to analyse continuous rigid frame briges reinforced by external presttessing ,and it can ignore the effect of the second stress. So, it can be capable of the analyses in the strengthening bridge by external presttessing using the method of controlling by flexibility and stress to set up the model of scathe,and,the method of external presttessing can ensure stress reserve of the main beam, to reduce effectively PrinciPal tensile stress, to renew line state of bridge structure and gradient. The effect of strengthenment was obvious and the reinforcement scheme was successful. The method provided an availability reference to the same bridge strengthened by external presttessing...