The Key Technology Research On Construction Of 112.5 M Steel Box Arch Bridge About Jing Ba Railway Crossing A Expressway

Taking the double-track 112.5 m steel box arch bridge of Beijing-Ba Railway across a certain expressway as the engineering background this paper studies the jacking construction technology and suspender tension process of the steel box arch bridge meanswell analyses the stress and deformation of the temporary structure and permanent structure in the construction process.The main research contents are as follows:(1)According to the geographic location engineering characteristics and other factors of the bridge a reasonable pushing construction method is studied and formulated.The design concept of jacking construction is selected as after the prefabrication and assembling of bridges by looking for open space near the existing line multi-point jacking with footsteps.(2)According to the construction technology of jacking construction and taking the bridge as the background the construction scheme of jacking construction is designed.The process of jacking construction is simulated by finite element software and compared with the field construction monitoring data.From the comparison results we can see that the monitoring has achieved the desired results.(3)According to the tension design scheme of suspender,the tension process of suspender is simulated by finite element software.According to this method the variation of tension force of suspender,stress,displacement of arch rib and longitudinal beam section in each tension stage is analyzed to guide field construction.