Experimental Study Of Reinforced Concrete Beams

Steel reinforced concrete construction is widely used in practical projects by virtue of its higher bearing capacity, higher stiffness and excellent seismic behavior. However, its calculation theory was developed a lot, but it can't satisfy the demands of engineering practice. At present, there is no design criterion for steel reinforced concrete construction in China. And there is no uniform design theory for steel reinforced concrete beams too. The primary contradiction is the different consideration of bond slip behavior between steel shape and concrete. So it is significant to study the mechanical behavior of bearing capacity, bond slip behavior, failure mode of steel reinforced concrete beams. This paper carries out experimental study on the mechanics performance of steel reinforced concrete beams, analyze the factors which affect the bearing capacity of steel reinforced concrete beams. And based on the experimental study, the applied calculation methods for structural engineers are proposed.Based on the experimental results of 2 push-out specimens and 8 steel reinforced concrete beam specimens, the affections of bond state, number of stirrups and shear connectors to the mechanical behavior of steel reinforced concrete beams are analyzed. Based on the ultimate intension theory of reinforced concrete beams and assumption that a plane section before bending and remains a plane after bending, formulas for the normal section bearing capacity calculation of steel reinforced concrete beams are derived. The proposed formulas agree well with experimental results. Using the bond slip constitutive relation curve achieved from push-out experiment, nonlinear finite element analysis for some specimens is carried out, and mechanical behaviors under different bond conditions of steel reinforced concrete beams are analyzed.