Bond Stress From the Rebar in the Straight Anchor Section on the Local Bearing Capacity of Concrete Under Anchoring Plates

In order to study the effect of the bond stress from the rebar in the straight anchor section on the local bearing capacity of concrete under anchoring plates, 30 pull-out tests of end-plate reinforced concrete were completed. The dimensions of the anchoing plate used in the test were 50 mm×50 mm×20 mm and 60 mm×60 mm×20 mm, the thickness of concrete protective layer c were 84 mm and 62.5 mm, the strength grade of concrete were C30, C40, and C50. The diameters of the reinforcement d were 25 mm and 32 mm and its embedded length l_ad was divided into 5 types in the test. The analysis results showed that the local bearing capacity of concrete F_l was related to axial compressive strength of concrete f_c, the relative embedded length l_ad/d and the thickness of the concrete relative protective layer c/d; F_l increased approximately linearly with the increase of l_ad/d (about 69% from the initial value), increased linearly with f_c (about 80% increase from initial value), decreased with an increase in c/d, the decreasing amplitude was up to 34%. Based on data fitting, the formula for calculating the local bearing capacity of concrete under anchoring plates with l_ad/d and c/d as independent variables was obtained.