Horizontal Clapboard Design Theory Reseach In Long-Span Prestressed Concrete Box Girder Bridge

Along with the concrete box beam in the project of the extensive application of concrete in the construction process and maintenance process of the release of the hydration heat caused by the temperature gradient, humidity diffusion form uneven humidity gradient caused by uneven shrinkage deformation, the creep of development and the load of box girder with horizontal clapboard have not neglect the effect. The purpose of this study is through the establishment of long span concrete girders local entities of the finite element model and the bridge of the plate and shell finite element model, and the research and analysis of the partition with horizontal pillar top beam section and cross section in the model of the hydration heat, shrinkage and creep, horizontal, vertical prestress, a prestressed force and distortion under the action of bearing law, in order to the partition with the concrete continuous beam in the design and construction of theoretical research and guidance. This article through to the box girder simulation, the main work and research results are:(1)This article through the simulation of the hydration heat three-dimensional temperature field, analyzes and summarizes the hydration heat temperature field distribution change rule and the influence of the stress of box girder, and puts forward the hydration heat caused by the decrease of the temperature gradient specific measures.(2)This article through the simulation concrete 3 d games, humidity analysis and research the humidity of the concrete shrinkage strain caused by diffusion rule changes, and probes into the concrete uniform drying shrinkage of concrete surface layer caused by deformation of the influence of tensile stress cracks. This paper analyses and discusses impact of shrinking stress factors, put forward the concrete shrinkage stress control the effective way.(3)Based on local beam section stress strain analysis, this paper analyzes the horizontal clapboard prone to box girder of stress concentration, and the area of the steel partition common configuration put forward some Suggestions. (4)Through the analysis and research box girder casting and maintenance in process of thermal effects, shrinkage effect hydration and creep effect of stress spikes period, and combining with local beam segment of the stress and strain analysis, this paper discusses the construction time by adjusting and other measures, abate the three comprehensive stress influence.(5)With horizontal clapboard through the box girder are studied by analysis of the horizontal distortion partition to control the distortion warp effect.