| An unprecedented scale in transportation has formed due to the great economy rise in China.Especially there is a massive increase in the amount of overpass bridges and viaduct bridges.In the road construction,the curved girder bridges can well adjust to the needs of line selection overall.At the same time,It shortens the extension of line to get considerable economic benefit;It can keep the road alignment smoothly for a driver and provide a feel of continuity in the road,avoid the disadvantages caused by the long line to improve driving safety and comfort.In addition,it can improve the coordination of road and surrounding environment to meet the aesthetic requirements.However,there have been so many overturning accidents in concrete continuous curved girder bridges in recent years.The reason is that the curve beam with" bend torsion coupling effect" will be influenced by various complicated factors including internal and external.The conclusions about beam body lateral disease is not uniform at present,including insufficient understanding of the temperature load,heavy traffic and vehicle overload effect,which make experts draw different conclusions in the research of curve beam bridges.The thesis firstly introduces the status of concrete continuous curved girder bridges,the development process,the inadequate in research and the points of repair and reinforcement.Secondly,the mechanical characteristics of this kind of bridges and the mechanical equation are deduced.Thirdly,the typical diseases of this kind bridges are introduced.In addition,the factors which influence the lateral displacement on the small radius curve continuous box girder need deeply research.The structural model of small radius curve continuous box girder bridge is built in the Midas/Civil,which is the large finite element software.The innovation of this article is as follows:analyzing the beam body deformation caused by its own factors and various external force under the original structure form and support mode through the sensitivity method;the calculations of each influence factor weights are used by the analytic hierarchy process;the main reason and secondary causes leading to the occurrence of lateral migration.According to the various influence factors of the proportion,the temperature effect coefficient value is suggested in the bearing capacity limit checking state.Finally,the rectification and reinforcement engineering of Anshan Sifangtai interchange bridge is taken as the engineering example.According to the mechanical and structural characteristics of the bridge,the feasible rectification and reinforcement scheme have been put forward,and a concise narrative about the details of the construction procedures and technical essentials during the processes of the rectification and reinforcement is made.Through the calculation and analysis,the system temperature increase every 5 ℃ leads to the increase about 1.1mm in lateral offset;Automobile overload increase every 10 tons results in the increase 0.3mm in lateral offset;the vehicle lateral offset increase every 0.5m,the lateral maximum offset will reach 1mm.As the influence of restriction condition,it will smaller lateral offset with more closer to the bridge bearing at the same section.The weight value of the system temperature on the lateral offset is the maximum(0.4201);the weight value of the partial load is the secondary(0.2652);the effect of dead weight is weak,the value is 0.0484.Through the above shows,we can find that the system temperature is obtained as the main factor which causing diseases,overloading of vehicle is the secondary factors.Finally,the feasible rectification and strengthening measures according to the disease cause are put forward.After the completion of the proof and the actual projects.PLC hydraulic jacks push synchronization technology can finish given work efficiency.So it can provide a reference for the application of this kind of bridges in the future. |
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