Structural behavior analysis of high strength steel-concrete composite girders

In order to study structural behaviors of high strength steel-concrete composite girders, 14 group-components models with different geometry parameters and material properties were built by using ANSYS software under deuce symmetrical loads at mid-span.The analysis result indicates that steel girder bears about 77.0% of whole vertical shear strength in plastic state, and the ratios of maximum and minimum values of mid-span deflections for different material strength girders in elastic and plastic states are 79.5% and 28.0% respectively; the ratios of maximum and minimum values of mid-span deflections for different transverse bar ratios and widthes of concrete slab girders in plastic state are 62.1% and 53.3% respectively; the ratios of maximum and minimum values of longitudinal slips for different material strengthes, widthes of concrete slab, transverse bar ratios and thicknesses of concrete deck girders in plastic state are 25.0%, 41.9%, 63.2% and 70.7% respectively.Therefore, increasing the strength and section size of steel is economic and reasonable method to increase the vertical shear strength of the girders; the steel and concrete strengthes affect little on the mid-span deflection of the girders in elastic state, and the transverse bar ratio and the width of concrete slab have larger effect on the mid-span deflection in plastic state; the geometry parameters and material properties of the girders have little effect on the longitudinal slip in elastic state, but the material strength, width of concrete slab, transverse bar ratio and thickness of concrete deck have obvious effects on the longitudinal slip in plastic state.