Analysis And Control Of Concrete Continuous Rigid Frame Bridge With High Pier And Large Span Prestressed Construction

Large span prestressed concrete continuous rigid frame bridge with its unique structural advantages, in the bridge construction in our country is a large number of applications, continuous rigid frame bridge closure analysis and control of the construction of more and more concern and attention. Continuous rigid frame bridge closure scheme, the closure temperature, and structural system of the main girder into bridge alignment and stress has a great influence. Therefore, for the long-span continuous rigid frame bridge closure sequence and thrust force analysis research has very important practical significance.In this paper, closure counterweight selection and setting method of continuous rigid frame bridge and the set of stiff skeleton were analyzed. Effects of closure sequences and closure temperature on structure alignment were also studied. And the reasonable method for jacking force was raised. Specific studies are as follows:(1) By consulting related researches, the stress characteristics of multi span continuous rigid frame bridges were summarized and the technical research of multi span continuous rigid frame bridges closure was also obtained. Based on the practical problems, this paper puts forward the research ideas.(2) The key technologies of continuous rigid frame bridge closure construction were analyzed. To prevent the deflection of girder and adjust the structure internal force adjustment, closure weight setting method was confirmed. And in order to guarantee the maintenance of concrete, enhance the cantilever connecting reliability, transfer horizontal jacking force and locking top pushing position, the set of stiff skeleton was also studied.(3) Qualitative analysis of closure sequences and closure temperature selection were carried out in this paper. Based on the existing research results, a calculation method for jacking force were proposed to get the ideal state.(4) Taking a six span prestressed concrete continuous rigid frame bridge as a case study, a whole bridge model was built by using finite element software MIDAS/Civil. The effects of different closing methods on relative height, the pier top longitudinal displacement and structure camber setting effect were analyzed.