Research On Design Technology Of Low Tower Cable-stayed Bridge

Low tower cable-stayed bridge is a new structure type, whose mechanical behavior hasthe characteristics of continuous girder bridge and cable-stayed bridge, but is not identical. Tofully understand the mechanical performance and technical characteristics and summarize thedesign method, keypoint and the application of the bridge, and provide an economic,beautiful, reasonable force and safe bridge type for the bridges span are in100~200meters,this paper study low tower cable-stayed bridge from the following several aspects.The main girder with large stiffness, main tower and long cable section, stay cables passthrough the top of tower, the relationship between tower, beam and cables, forcecharacteristics of cable tower saddle area are analyzed in this paper. The main achievementsare as followings:1. Through studying the mechanical principle and calculation theory of low towercable-stayed bridge, the internal force and deformation of the structure were calculated.Through the research on the effects of material nonlinearity and structure geometricnonlinearity on the cable-stayed bridge, the processing methods for nonlinear problem areobtained.2. The different main girder stiffness, cable tower height, cable sectional area, thedistribution of the cable area are calculated and analyzed through finite element analysis, theimpact of these parameters on the whole structural stiffness and internal force was obtained.3. By means of studying the short tower cable-stayed bridge aperture arrangement,structure system, the choice of main girder cross section and the design method of the cabletower and stay cables, the specific value range of short tower cable-stayed bridge was given.4. The bridge cable saddle section was analyzed by using ANSYS and the changecharacteristics of stress was got.5. Through using a variety of structural analysis programs, this paper analysedmechanical dynamical behavior of PC short tower cable-stayed bridge structure, thereasonable state of stiffness matching, choice of depth-span ratio and inclined cable segmentlength was got.The research contents of this paper has a very important significance to the low towercable-stayed bridge design theory, analysis method and the development of bridgetechnology.