Research On Mechanical Properties And Design Length Of Steel-concrete Joint Section Of The Long Span Cable Stayed Bridge

Hybrid Beam Cable-Stayed Bridges is a new type of cable-stayed bridge.It has excellent structural performance,great leap capacity and beautiful shape,so it has a very promising future.The steel-concrete joint section between the main span steel box girder and the side span concrete box beam is the key part of the hybrid Beam Cable-Stayed Bridges,which needs to be studied in depth.The length of the steel-concrete joint section of the four bridge of Tuojiang River is short in the same type of bridge,and the problem of internal force transfer and transition is more prominent.Taking this bridge as the engineering background,the analysis of the mechanical performance and the design length of the steel-concrete joint section is of greater engineering value and theoretical significance.This paper mainly uses Midas/Civil and Abaqus finite element software to carry out simulation analysis.The main work and results are as follows:(1)The development and research of the steel concrete joint section are introduced;The related theory of steel concrete joint section is expounded;The internal force transmission mechanism of the steel concrete joint section is analyzed;The structural characteristics of the steel concrete joint section have been clarified.(2)Combined with the actual construction process in the four bridge and used Midas/Civi to establish the full bridge model:analysis of steel-concrete construction stage with internal force;steel-concrete operation stage internal force combination at different loading conditions and stress value,the internal data extraction of axial force,shear force and bending moment reached the maximum of unfavorable conditions.(3)Using Abaqus finite element software to set up the local model of steel-concrete joint section,determine the most unfavorable working condition,and analyze the stress distribution and transmission condition of the steel-concrete joint section under the most unfavorable working conditions.(4)By comparing and analyzing the local model stress of the steel-concrete join section with different design lengths in the same structure,the reasonable range of design length of steel-concrete joint section under the action of axial force,shear and bending moment alone is put forward.