Stress Analysis Of The Flange Plate Of A Long Cantilevered Concrete Box-section Girder Bridge

With the development of transportation and the use of land and resources,urban space problem is more than urgent.Because of the long-cantilever concrete box girder is increased the width of the flange plate and increased utilization of the bridge space,so it get rapid development.However,the code for Design of Highway Reinforced Concrete and Prestressed Concrete Bridge design of China(JTJGD062-20012)is suitable for the calculation of short cantilever driveway the flange and not the long cantilever driveway the flange.Based on the finite element method,the element calculation software of the ANSYS is applied and the long-cantilever concrete simply supported box girder model was established,to the stress analysis of the long-cantilevered flange plate under the static loads,with the influence of the section form of flange plate and the transverse prestressing taken into account,to discuss the distribution of the long-cantilever concrete box girder flange plate bending moment,the semi-infinite plate effect of box girder end flange plate and the infinite plate effect of box girder across flange plate.At the same time,based on the load effective distribution width calculation theory of long-cantilever flange plate,to the stress analysis of the load effective distribution width of box girder across flange plate,with the influence of flange plate grade,thickness,length and load position taken into account.And based on the least square method,the computational formula of load effective distribution width of the Long cantilever concrete box girder across flange plate is fited with the matlab numerical calculation software.However,long-cantilever flange plate is not only owning hogging moment but also sagging moment,so the new concept of sagging moment ratio is defined,and using matlab calculation software to fit the computational formula of sagging moment ratio to calculate the sagging moment of flange plate.At the same time,the impact coefficient of box girder cantilever flange plate is1.3 in the Chinese code “General Code for Design of Highway Bridges and Culverts”.However,with the increase of the length of the flange plate,its dynamic characteristics will tend to be complex.Compared with short cantilever flange plate,long cantilever flange plate dynamic magnification coefficient will produce a series of change,and the dynamic amplification effect of the sagging moment and hogging moment is not the same,so quarter vehicle model with six parameters and two-freedom is established,and calculating the dynamic magnification coefficient of long cantilever flange plate with the influence of road roughness,transverse pres-tress,speed and flange plate section parameter to provide the reference for the long cantilever flange plate reinforcement design.