Research On Reinforcemen Rigid Frame Arch Bridge By Steel Plate-concrete Composite Structure

Our country has developed the rigid frame arch bridge,and is widely used in bridge construction since the 70 s of the twentieth century.After the reform and opening up,the rapid development of economy accompanied with the increase of traffic volume,which makes heavy load and overload more frequent in site.Some of the arch bridges in service have long been in operation of a disease state for a long time,which poses a threat to the comfort and safety of pedestrians.So it shall be avoided the expensive cost of demolishing old bridges and rebuilding.An effective reinforcement method is shall be explored to repair and reinforce the rigid frame arch bridge.It has very important practical significance.The main work of this thesis,firstly,summarizing the structural characteristics of the arch bridge,analyzing of typical diseases in each component,and summarizing the common reinforcement methods of rigid frame arch bridge.Secondly,establishing the model of an active rigid arch bridge in service by using the finite element analysis software ANSYS,at the same time,according to the static and dynamic load test data of the bridge before reinforcement,correcting the parameters of the finite element model,and obtaining the finite element model which can reflect the actual operation condition of the bridge,then applying the parameter is to Midas FEA to analyze the bearing capacity of the rigid frame arch bridge.Third,establishing the reinforcement model according to the existing reinforcement scheme and the static and dynamic load test data after reinforcement,through comparison and Analysis of the results of calculation and practice,good fit of deflection and stiffness.Verifying again the reliability of the modified model before reinforcement.Fourth,from the improvement of the rigid arch bridge integrity,proposing and adopting the new reinforcement method which.And using the Midas FEA to build a reinforced finite element model based on the correct model.Through calculation results and contrasting reinforcement effect of the two methods.Through the above analysis,the method of steel plate-concrete composite structure can greatly improve the integrity of the bridge,the safety factor is increased obviously,the deflection under static load is well controlled.Two reinforcement methods are compared by calculating the data,the results shows that the stiffness and strength of the rigid-frame arch bridge are obviously improved by the steel plate and concrete composite structure.It is proved that the reinforced concrete composite reinforcement method is more advantageous than the original reinforcement method.It provides reference for the reinforcement of similar Bridges in the future.