Corroded Reinforced Concrete Beam Inclined Section Shear Performance Study

Reinforced concrete corrosion is common phenomenon in reinforced concrete member structure, the corrosion of reinforced concrete is the most main factors that cause structural damage. The following sums up three aspects about the influence factors of reinforcement corrosion on the structural durability: one is such as rust corrosion after material makes the external surface of the concrete volume expansion, thus result in the crack of the concrete cover along along rebar concrete section appear damage phenomenon; 2 it is rust after make the component of bond between steel bar and reinforced concrete role in greatly reduced; Three is the effective cross section of reinforced concrete beam after corrosion is reduced, the bearing capacity of the corresponding also decreases. Due to the small diameter than the diameter of a longitudinal reinforcement and stirrup near the protective layer, its corrosion degree tend to be more serious than other steel. At present, both at home and abroad of corroded reinforced concrete members, especially on equipped with bending rebar corrosion of oblique section shear beam relatively little research. In this article, according to the research results and combined with related reference test established the bearing capacity of corroded reinforced concrete inclined section shear model, this paper set up six reinforced concrete beams to bearing capacity test of all beam stirrups corrosion rate is not the same, the results in this paper, the shear bearing capacity model is set up for validation. At the same time, this article also experimental beams with finite element analysis, specific for the following research work:(1) this article summarizes the research status quo of corroded reinforced concrete members forecast model and mechanical properties of the research status, and also discusses the shear bearing capacity of corroded reinforced concrete beam problems existing in the research.(2) based on the references in the test of the existing research results, on the basis of combining the shearing mechanism of ordinary reinforced concrete beam and limit equilibrium principle, and analyses the influence of stirrup corrosion after adverse effect on the shear strength of reinforced concrete and specification of the bearing capacity of shear bearing capacity formula and introducing influence coefficient alpha the resulting formula to calculate the shearing resistance. In this paper, combined with existing experimental results in the literature and the inductive statistics to get a set of data, influence coefficient is obtained by linear analog calculation formula of alpha. In addition, the limit equilibrium method to consider the shear limit state of reinforced concrete beam section shear under the action of bending moment and shear force, in the failure stage beam by concrete is divided into two parts and inclined cracks by abdominal muscle, longitudinal reinforcement bolt pin force, etc.(3) by setting stirrup corrosion rate and the component of the shear span ratio, shear performance of inclined section carries on the analysis and research, the two variables is obtained by experiment, the bearing capacity of reinforced concrete shear effect, at the same time, by setting the experiment of this paper, the mathematical models of shear bearing capacity of corroded reinforced concrete is verified, the results show that the established in this paper, formula to calculate the shearing resistance has a certain credibility. In addition, the test also studied the test beam crack development and failure process of the change of deflection, experimental results show that the bearing capacity of the component and decreased with the increase of stirrup corrosion degree, bearing capacity and stiffness of the beam gradually reduce with the increase of corrosion rate, stirrups corrosion cracks generated after the shear strength of the tested beam has a great influence.(4) in this paper, in order to test the bearing capacity of the beam and the crack deformation and crack propagation graph, after using the ANSYS finite element analysis software for this component is analyzed and a separate model, simulation of steel and concrete at the same time units are using spring element to simulate the bond performance between them.