Bearing Capacity Of Corroded Reinforced Concrete Beams And Finite Element Simulation

Since the advent of reinforced concrete structure,it was widely used because of its prominent advantages and excellent performance in bridge engineering. But with the passage of time and the change of environment, the reinforcement corrosion that one of the important factors affecting the service life of use of reinforced concrete structure got people’s attention gradually. Reinforcement corrosion could lead to the performance degradation of the concrete structure, reduction of reliability and working life. Recently, people has paid attention to the service life of the structure, reinforcement corrosion was widely researched as a hot issue.This paper, under the condition of the shear span ratio and corrosion rate and based on predecessors’ work, and then designed a set of experiment about the bearing capacity of the corroded reinforced concrete beam. Test was divided into two groups, one group is the shear span ratio of3.0BM1group, another group of shear span ratio of2.4BM2group, each group had a root of beam uncorroded by comparison. Using the electrochemical accelerated corrosion method makes different corrosion rates. After the test of the bearing capacity, the relationship of components in the flexural bearing capacity, crack distribution, cross section strain distribution and the load-displacement were analyzed.Using the finite element method simulated the test process based on considering reinforced concrete bond-slip. Through the corroded reinforced concrete bonding-slip constitutive relation and the relation of cohesive force reduction coefficient along with the changes in the rate of corrosion, the load-displacement curve expression of the corroded reinforced concrete bonding element was deduced.Analyzed the related data of bearing capacity and compared with the test results, it was concluded that the maximum error of the theoretical value and experimental value was9.81%, showed the effectiveness of test. The crack pattern fracture distribution by numerical analysis was compared with the experiment, and it was concluded that the crack tendency was consistent, with the increase of corrosion rate, the beam body damage status changed from the shear failure to the bending failure gradually.The load and strain curves of component were obtained, it was concluded that the steel strain always lagged behind the concrete strain in the elastic phase, and the corrosion rate didn’t affect the cracking load of the component. Through the graph of cohesive force distribution along the beam body, it was concluded that cohesive force appeared the wave distribution along the direction of the beam’s length, when the load was small, the largest bond appeared near the load point. And then when the corrosion rate was close to10%and the load reached about70%of the ultimate load, the cohesive force distribution of the load point along the tie-beam appeared a straight line trend, and the higher corrosion rate, a trend that more and more obvious.