The Study On Mechanical Performance Of Steel-concretecomposite Segment For Long Span Hybrid Girder Cable-stayed Bridge

This paper relies on the background of the Yangtze River Bridge project Yongchuan, using Midas / FEA and Midas / Civil mixed steel- concrete cable-stayed bridge girder segment mechanical performance analysis. For large span hybrid girder bridge, with a main span steel girder segment combined with the side span prestressed concrete beams between the important part is mixed Bridge. Reliability combined segment position and structure of rationality, is a key issue affecting hybrid girder bridge design and construction. In considering the mechanical properties of steel-concrete segments, the function should be able to make a variety of internal forces(axial force, bending moment, shear force, torque) between the steel beam and concrete beams, reliable, smooth delivery. In the two-part structure should make concerted beam shape, as far as possible to avoid the rigidity and strength of mutation, combined segment ensure good fatigue resistance and durability.Many scholars at home and abroad for the current steel concrete composite section force the issue a lot of research work characteristics, obtained many ripe theory. Based on previous studies, the main contents of the following studies:â‘  cable-stayed bridge for the Yangtze River in Chongqing Yongchuan space Sorbian home, not the traditional Sorbian plane home, spatial effects and steel concrete composite bridge segments are obvious. For this feature, on the mechanical properties of steel concrete composite sections spatial finite element analysis;â‘¡ using Midas / Civil establish full bridge model cantilever bridge in the process of assembling the steel concrete composite construction segment internal force change; and before and after closure, changes in mechanical properties of the system before and after the conversion process steel concrete composite section, and extract the most unfavorable load working conditions;â‘¢ large finite element software Midas / FEA steel concrete composite sections established by the finite element model of the space, the material properties of steel-concrete segments, boundary constraints, etc. simulation, in order to calculate the theoretical results coincide with the actual situation;â‘£ full bridge finite element model based on the extracted Bridge construction phase and the operational phase of the load of the most unfavorable conditions, to carry out detailed analysis applied to physical simulation model to explore the steel-concrete combination of stress and strain distribution segment.