Research On Shear Capacity Of RC Beam Strengthened With Externally Prestressed Steel Wire Rope

The traffic demand of modern highway can’t be content, because the shear carrying capacity of a part of the domestic old bridges can’t be sufficient. The scientific and reasonable reinforced method in shear is an important research in the field of bridge reinforcement.In the paper, on the basis of the shear experiment strengthened with externally prestressed steel wire rope, the shear carrying capacity of RC beam strengthened with externally prestressed steel wire rope was researched with the aid of the finite element method in the concrete strength grade, shear span ratio, stirrup ratio, longitudinal steel ratio, prestressing, and steel spacing.The research content included the model validity analysis and parameter sensitivity analysis. The model validity analysis indicated that the theoretical yield value of reinforcement beam was close to the experimental value, the theoretical ultimate value was slightly smaller than the experimental value. With the load increasing, the change trend of theoretical deflection value was consistent with the change trend of experimental deflection value at the load point, and the theoretical value was less than the test value.The parameter sensitivity analysis indicated that the shear capacity of reinforcement beam was improved with concrete strength grade increasing, and the change trend was according to the linear rule. With the shear span ratio increasing, the shear capacity of reinforcement beam was reduced gradually. The yield load and ultimate load of reinforcement beam were advanced along with the increase of stirrup ratio. The yield load of reinforcement beam was in a linear relationship with stirrup ratio in the range of0.25%～0.4%. The ultimate load of reinforcement beam was in a linear relationship with stirrup ratio in the range of0.25%～0.35%. With the longitudinal steel ratio improving, the shear capacity of reinforcement beam was improved in the linear rule. The shear capacity of reinforcement beam was improved gradually along with the increase of prestressing. The shear capacity of reinforcement beam was decreased with the increase of steel spacing, and the shear capacity of reinforcement beam was decreased in the linear rule in the range of200～350mm.