Finite Element Analysis Of A Prestressed Concrete Curved Continuous Box Girder With6Cells

Zhantian Lake in Changde City is a tourism scenic area. The bridge on the east bank of the lake with the total length2100m is curved and symbolizes a huge dragon. More than ten continuous beams of the bridge is pre-stressed concrete curved continuous box girder with6cells. The substructure of the bridge is in the lake and the geology condition is poor. The17th continuous girder is representative and selected to study its deformation and stress condition. The main work and the results are as follows.1. The finite element analysis method of the superstructure of the bridge is studied based on the collecting and studying the relevant information at home and abroad. Grillage method is used and a three dimension finite element model with seven stringers, five real cross beams and more than hundreds of virtual cross beams is established. The simplified modeling approach of the prestressed tendons curved in space is studied and used in the establishing of the finite element model and good effect is obtained.2. Considering the process of construction of the beam, the analysis of the deformation and stress characteristics of the17th continuous beam under dead load, live load and the both is completed. The influence of concrete shrinkage and creep on the deformation and stress characteristics is studied. The results show that under the action of the main combination the deformation of the bridge is small and the stress condition is reasonable benefiting from the prestress and their influence of concrete shrinkage and creep on the deformation and stress characteristics is not large.3. Finite element analysis of the bridge under the action of wind and temperature has been finished. The results show that the influence of the wind on the bridge is small and can be ignored. The stresses caused by rising or falling the temperature30℃for the whole bridge is not large, but the lateral reactions of the bearings are quite large. The reactions of the bearings and the deformations of the girder caused by the sunshine temperature difference are smaller, but the stresses are larger. 4. The main differences of the curved girder from the straight one is summarized. Besides the difference of vertical reactions of the inside and outside bearings under the action of vertical loads, the lateral reactions of the bearings of the curved beam would occur under the action of vertical loads and the rising or falling the temperature for the whole bridge and more attention should be paid.5. The bearing capacity of the pile foundations of the bridge has been checked. The results show that the demands of the resistance of the pile foundations are satisfied.