Research On The Shear Resistance Of Box Girder And The Shear Distribution Of Web

Due to the box section has the unique advantages compared to the other sections; it hasbeen widely used in pre-stressed concrete bridge. But this type bridge exists the typical crackphenomenon, especially in the web of diagonal cracks, seriously impacting on the use ofsecurity and the life of the bridge. There are many reasons for Cracks, which the box girdershear is a very important issue. This paper combines the mechanical characteristics of the boxbeam, mainly analysis the box girder shear capacity and the shear distribution to explore thisissue. I hope can be helpful for the design and construction of similar bridges.1、This article lists the national norms for the shear formula, and Xi-Tong high-speedexpansion project which Weihe Bridge continuous rigid frame is the part of it is used for thecalculation example. According to the different specifications, the factors which affect shearcapacity are comparatively analysis. The results show that the result of China highway bridgedesign specifications is closest approach the British Standard, the calculated value is largestdifference compared with the Railway Code. Changing parameter values for furthercalculations to analysis the different norms in the calculation of shear capacity.2、Based on thin-walled theory, using the displacement compatibility conditions, thispaper analysis when the multi-room thin-walled box girder web is in the bent state, the sheardistribution of the middle and side web. get the conclusion that the shear webs passing-shearlarger than the edge of web delivery, and the absolute value of the symmetric box girdercross-section of the two side webs shear values are equal. Therefore, in the design of thebridge, each web should be load calculation.3、ANSYS finite element is used to establish the Weihe bridge local entity model,through comparison the various conditions under principal tensile stress value, analysis thevertical pre-stressing impact on the shear behavior of box girder webs; This paper calculatedvertical pre-stressing partial bit webs under the force of change, the measured and theoreticalvalues were compared and found that the vertical pre-stressing bars smaller partial verticalstress on the structure of the smaller changes in principal stress will not have a greater impact.