Research On Bending Performance Of New Type Partially Outsourced Concrete Steel Composite Beam

The new type of partially encased concrete steel composite beam studied in this paper is a kind of bending member formed by using partially encased concrete steel.The new composite beam has excellent bending performance such as high bearing capacity,rigidity and ductility,it also has good economic effects.This paper systematically studies the bending performance of this new type composite beam through theoretical analysis and fine simulation with large-scale finite element software.The main research contents and results are as follows:First of all,based on the engineering practice of large-scale design and research institutes,combining the characteristics of steel structural beams and composite structural beams,a new type of partially encased concrete steel composite beam(NPSRC for short)is proposed.Through the finite element analysis software ABAQUS,a nonlinear analysis model of NPSRC is established.The development of stress and deformation of each part of the component,the relationship curve of load-deflection and the law of the distribution of strain along the height of the section are discussed preliminarily.At the same time,the stress and deformation characteristics of the new partially encased concrete steel composite beam are clarified,which lays a good foundation for further software analysis and theoretical calculation.By comparing with the experiment,the accuracy of the finite element analysis method in this paper is verified.Secondly,this paper changes the six parameters of concrete thickness,concrete strength,steel strength,flange thickness,web thickness and section steel height to establish a series of nonlinear finite element models.At the same time,the influence of parameter changes on the bending capacity,deflection and ductility of the new composite beam’s normal section is studied.Finally,based on the finite element analysis results and theoretical calculation assumptions,using the basic structural theory and referring to the relevant codes and calculation methods in the literature,a theoretical calculation formula for the bending capacity and deflection of a new partially encased concrete steel composite beam is proposed.Combined with the content of the full text,the section design and construction measures of the new composite beam are proposed.