The Study On Bearing Capacity Evaluation Of Reinforced Concrete Girder Bridge Based On Deflection

With the development of transport, the load grade of highway access in our country is increasing. As a result, many of existing bridges can not achieve the requirements. The carrying capacity assessment of small and medium-span reinforced concrete bridge which account for most, has become one of the important contents of the study about the bridge safety. To determine whether the load of an old bridge to meet the load classification and to assess its work status are the premises of the work to reinforce the bridges.Based on domestic and international specification’s Stiffness formula and the relevant research results,the paper makes a Comparative Analysis of reinforced concrete T-beam, and the Highway of Reinforced Concrete and Prestressed Concrete Bridge Design Code(JTG D62-2004)Stiffness formula are recommended to predict and assess Bearing capacity of bridges. According to the relationship between load, flexivity, reinforcement ratio and stiffness, the equation of deflection and reinforcement ratio is established for the prediction of structure’s Nominal reinforcement ratio. the method of prediction for Nominal reinforcement ratio is verified by the use of finite element software and it is clear that the prediction method meets the needs of Engineering accuracy.using an existing old bridge as the object of study, the dissertation predicts the load level factors of the bridge, which is equivalent to the existing highway load grade I, and evaluates the loading bearing capacity quantitatively by using the calculation of load transverse distribution factors and the method of predicting the reinforcement ratio. The results indicate that the evaluation results of method which this article used coincide quite well with load testing results. Research results can be applied to the prediction of small and medium-span concrete girder bridge bearing capacity.