Static and Cyclic Tension Behavior of Post-Installed Rebar after Exposure to High Temperature

Abstract

In order to investigate the static and cyclic tension behavior of post-installed rebar along with cement-based adhesive that is adopted after exposure to high temperature, a three-phase experimental program has been carried out and two typical embedment depths, 10d and 15d are designed. The surfaces of specimens are firstly heated up to 800°C, and then the residual strength at different temperatures of cement-based adhesive has been studied by consequent static pull-out tests. Experimental results show that the tensile strength has a significant reduction at elevated temperatures compared with that of room temperature. The cement-based adhesive has almost lost its full bond strength when the temperature exceeds 350°C. Finally, the bond performance of cement-based adhesive under cyclic loading has been further tested and analyzed. It is found that both 10d and 15d specimens have failed abruptly with rebar pull-out. The employment of long embedment depth has been verified to be an effective method to improve the bond performance of cement-based adhesive under static and cyclic loading. Static numerical investigation indicates that the bond stress distribution is not uniform along the embedment length of post-installed rebar at different temperatures of cement-based adhesive. The temperature-dependent tensile strength prediction has also been obtained based on the experimental data.