Experiments And Theoretic Research On Uplift Effect Of Steel-Concrete Composite Beams

Steel-concrete composite beam is a new type composite member in which steel and reinforcement concrete slab are integrated by connectors to take advantage of the tension and compression.Due to the advantages of steel beam and reinforced concrete beam,and notable benefits of society and economic.Even though the studies of steel-concrete composite beams are extension,there is still much deficiency in design and actual application.Based on this,the research on the vertical uplift effect for steel-concrete simply supported composite beams is presented.Through the test of five simply supported specimens for steel-concrete composite beams,The mechanical properties of them in static load are tested.The influence factors such as the degree of shear connection,the arrange of studs and the rate of steel are concideration.The relative slip,vertical uplift displacements and vertical uplift forces of studs are obtained.The stiffness coefficient of level resist slip and vertical resist uplift of the studs are received through theoretical analysis and experimental method.Based on the theory of elastic,the theoretical calculate mode of interaction for simply supported steel-concrete composite beam is established.the expressions to calculate the vertical uplift force of steel-concrete composite beams along the beam length are received,and the uplift force subjected to stud can be obtained by proper integral in the space of the studs,the expressions to calculate the deformation of steel-concrete composite beams are established considering the influence of vertical uplift effect.Through compare and analysis,the values from this theoretical method are in good agreement with experimental results.According to the uplift forces of the composite beams,the capacity of stud to resist the uplift is analyzed theoretically,six failure modes for stud to resist the vertical uplift are proposed,and the carring capacity to resist the pulling of the stud is calculated,the design to resist vertical uplift and constitution measures are suggested.It will be helpful to the further experiments and theoretic studies on the vertical uplift effect and anti-uplift of steel-concrete composite beams.