Distortion-effect Analysis Of Pre-stressed Concrete Skewed Box-section Girder Bridge

The cross section shape of box girder is geometrical changeable, once under the bias load or anti-symmetric loading, torsion and distortion produced at the same time. So far, as for the calculation method of distortion angle and distortion stress, domestic and foreign scholars perform a lot of research and achieve corresponding results. While the analysis of skew bridge is not a lot, this article carried out the relevant research work to distortion effect of pre-stressed skew box girder-bridge under static load and moving load.Simply supported and three spans continuous skew box girder bridge models are built by using the finite element software ANSYS in the thesis. Firstly of all, analysis the longitudinal distortion effect of pre-stressed concrete supported and three spans continuous skew box girder bridge which under the weight of the load and obtain the most disadvantage section of the skew bridge. And then set up a serious of similar box girder mode have been obtained in the thesis, analysis the change regulation of the longitudinal distortion angle of the intersection between roof and web when parameters vary. Finally, set up a serious of similar bridge and vehicle mode have been obtained in the thesis, vehicle mode is six parameters and two degree of freedom, then analysis the distortion effect change regulation of the most disadvantage section subjected to three different traffic routine and three different axle load and six different vehicle speed, and obtain the following results:There are some differences in unfavorable section’s distortion effect between the simple and three-span skew box girder bridge. Three quarters-span section is the most unfavorable one in the simple skew box girder bridge, and with the change of the parameters, it can be seen that driving speed, wide-span ratio and pre-stressed horizontal have more effect to the distortion effect. The mid-span section of the side span and mid-span is the most adverse section in the three-span continuous skew box girder bridge. Three are some large differences in mid-span’s distortion effect of different span in the impact of the differences parameters. And the distortion angle in each mid-span is not obvious with the change of driving eccentric and traffic conditions.