Study On Simplified Composite Beam Model And Mechanical Performance Of Three-dimensional Frame For Considering Section Stiffness

Steel-concrete Composite beam is a structure type with concrete slab and steelbeam connected by shear connector to bear load together. This kind of structure typecan resist the lift displacement and relative slip at the interface, it can cut down steelmaterial consumption, magnify rigidity and integrality as well as the stability comparedwith steel beam without shear connector. Giving full play to the compressiveperformance of concrete and the tensile performance of steel, this kind of structure typeis one of the structure types with great development prospect. Recent years, the majorityof Composite beam calculation model is consist of slab with a certain width added tothe top flange of steel beam, theoretical derivation and experiment research are bothconducted. Using the conducted experiment, simulate the degree of shear connectorefficiently by reasonable simplification of the Composite beam section, it will greatlyreduce the difficulty of modeling and integral analysis when conduct finite elementanalysis to composite beam framework model based on a simplified model. This thesisis aimed at present a new simplified composite beam model in order to provide the basisto the design and research of composite beam, this work is with great theoreticalsignificance and application value. The Main Research Contents are as follows:(1) In order to form the rudiment of simplified model, computing methods such asreduction of stiffness and effective width as well as equivalent section in conductedresearch result are analyzed first, a imagine of simplified calculation that reflect thesection stiffness and bending strength of composite beam is presented, for ease of thefinite element analysis on three-dimensional steel frame.(2) By reference to the conducted experiment, a steel frame model is built withABAQUS. The stress and deflection at span centre of the frame beam without floor slabare obtained through theoretical computation when it bears the uniform load, and theresults are compared between the finite element analysis and theoretical computation toverify the accuracy of the finite element model. On this basis, the stress, strain,deflection and lateral displacement of the beam in the three-dimensional frame areanalyzed when it bears the uniform load.(3) The mechanical performances of integrated frame are analyzed by usingsimplified model, verify the rationalization and availability of the simplified model bycomparing with the experiment results, the relationship between the thickness of the equivalent steel slab and the degree of shear connection between the concrete slab andsteel beam is discussed, and the influence on the mechanical performance of framebeams is analyzed when the thickness of the slab and the span of beams are changed.