The effect of anchor inclination angle on the tensile strength of chemically bonded anchors in steel fiber-reinforced concrete

In this study, the effect of inclination angle on the tensile strength of the anchor is investigated experimentally for inclined chemical anchor applications to steel fiber concrete. As variables, three anchor inclination angles (0°, 15°, and 30°), three fiber volume ratios (0%, 1,5%, and 3%), and three anchor embedment depths (40 mm, 60 mm, and 80 mm) are discussed. The main evaluation criterion for outputs is the anchor tensile strength. The study aims to determine the effect of each variable on the anchor strength one by one, as well as to examine their interaction with each other. In this context, "Box-Behnken" experimental design approach was used to determine the test points, and 17 test points were determined. Chemical anchorage was applied to the concrete cube blocks of 350x350x250 mm dimensions prepared for each test point. In these samples, the concrete class is C30, the anchor bar is a deformed reinforcing rebar with 8 mm diameter and S420 strength, and the chemical adhesive is an epoxy acrylate-based, two-component material. Load-displacement curves, maximum tensile forces, and fracture patterns were determined by applying tensile tests to the prepared samples. It is concluded that the tensile strength decreases by approximately 16% and 32%, respectively, for 15° and 30° inclined anchorage applications compared to 0° anchorage applications. The effect of the fiber volume ratio on the tensile strength of the inclined anchor remained limited, and the tensile strength for 3% fiber ratio increases approximately 11% compared to 0% fiber ratio.