Study On The Influence Of Structure Performance Of Concrete Shrinkage And Creep Of Mangniu River Bridge Widening

After the reform and opening up,the domestic economy goes into a full recovery stage,with the economic growth,the social calls for more stringent requirements to transportation industry.So the total transportation in city maintains sustained growth,the traditional transportation infrastructure to some extent limits the development of transportation industry.Therefore,strengthening traffic infrastructure construction has become one of the major problems facing the transportation industry.Pavement,bridge deck widening and reconstruction of old bridge is an important measure to increase traffic.In this paper,mangniu River Bridge Widening Project,considering the effect of concrete shrinkage,creep and other factors on the new and old bridge structure affected by stress and distortion,which has a certain reference value to the similar bridge reconstruction project widened.During the rebuilding of old bridge,it is necessary to overlay the concrete on the basis of the original bridge structure,as time goes on,the new concrete and the old concrete have different shrinkage and creep due to the different internal stability,which lead to the internal stress and affect the stability and safety of the bridge.This study takes the T beam bridge as an example to study the shrinkage and creep effects and to provide the theoretical support and improvement measures for the reconstruction of the old bridge.This paper uses Ansys theory and finite element analysis of old bridge transformation process,concrete shrinkage and creep difference of new,old bridge structure has the influence two aspects of force and deformation of the stress mainly concentrated in the new and old bridge junction and new T beam edge beam,main beam will produce little intrinsic should in force,axial force,shear stress and bending moment of verification,shall be based on the bridge side beam;difference of deformation is mainly concentrated in the new and old bridge connecting edge beam,the difference of deformation caused by easy longitudinal cracks of bridge deck,which leads to the safety of the bridge at the junction,so it needs to take to increase the steel mesh or choose appropriate measures to reduce the connection time of new and old bridges side beam deformation;whether it is caused by the difference of shrinkage and creep internal stress or deformation difference,will have a negative iMPact on the bridge stability and safety.In order to strengthen the stability of the bridge and reduce the internal stress concentration and deformation difference caused by the shrinkage creep difference between the new and old concrete,this study analyses the influence of the connection time on the shrinkage and creep ofconcrete,the result shows that prolonging the connection time can reduce the difference of shrinkage and creep between the old and new concrete,thus enhancing the stability of the bridge.