Experimental study on shear behavior of corroded reinforced concrete beams with low shear span ratio

Corrosion of stirrups in reinforced concrete beams can easily cause performance deterioration and even failure of concrete structures. This paper presented an experimental study on the shear performance of concrete beams which had corroded stirrups of HRB400 and low shear span ratios that were less than 1.5. A total of eight concrete beams was casted and divided into two groups according to the shear span ratio of 1.0 and 1.5. After the tests of these beams, a comparison of the performance of steel bars and load carrying capacity of beams without and with corrosion in stirrups was made, which led to the following conclusions. The effective corrosion ratio of stirrups should be defined according to the extent of corrosion of the bars in the vertical parts of stirrups, which can more accurately reflect the performance and section loss of corroded stirrups. The shear load carrying capacity of concrete beams does not significantly decrease when the corrosion ratio is less than 20%, while the shear capacity drops significantly when the corrosion ratio is beyond 30%. When the shear span ratio of these experimental beams is less than 1.5, the corroded stirrups has little effect on the decrease of shear capacity of beams, which is mainly because the corrosion cracks in the beams lead to the deficiency of integrity of the core concrete surrounded by stirrups. © 2019, Editorial Office of Journal of Building Structures. All right reserved.