Study On The Theory And Method Of External Prestressing Reinforcement Of Skew Girder Bridge

With the increase of operating time and traffic volume, a lot of skew girder bridgeshave appeared different degree of cracking and the damage of the bridge deck system. Inthis paper, based on the current situation of skew girder bridge damage reinforcement,through analyzing the regularity of skew girder bridges (especially the side beams), theexternal prestressing reinforcement method of skew girder bridges is proposed. The mainresearch contents are as follows:1. This thesis is based on theories and researches of skew girder bridges and theexternal prestressing reinforcement from domestic and abroad, by comparing theapplication status quo for external prestressing reinforcement method in orthogonal girderbridges and skew girder bridges. The characteristics, purpose and significance for theexternal prestressing reinforcement of skew girder bridges are proposed, as well as thedistribution principle, main points and arrangement of prestressed tendons.2. According to the design theory of skew girder bridges, analyzing the basic structures,the mechanical characteristics and the influence factors of skew girder bridges, the suitabletheories and methods for the skew bridge reinforcement mechanical properties arerecommended.3. The article focuses on the30m-span prestressed concrete simply supported girderbridges in the Standard Drawings as the research object, and analyzes the distribution andthe variation of bending moments when the skew bridge parameters changes, then comes upwith the stress performance parameter analysis method for the skew girder bridge.4. Based on the skew girder bridge load characteristics and layout principles ofexternal prestressing tendons, by comparing the difference value percentage of bendingmoment between the direction of the obtuse angle and the acute angle when skew girderbridge parameters changes, the line segment as a design element beam in externalprestressing tendons (Including the location and length of the horizontal section) of externalprestressing reinforcement design method for the skew girder bridges is built, the scope ofapplication is given, and the offset influence factors of the external beam line segment isanalyzed. 5. According to the external prestressing reinforcement design method for the skewgirder bridges from this paper, all checking indicators of the skew girder bridge which theskew angle is60and wide-span ratio is0.4before and after reinforcing are compared,verifying the reasonableness and feasibility of the proposed method.