Bond shear modulus of reinforced concrete at high temperatures

Abstract

The effect of fire and high temperature on the behavior and properties of concrete has drawn considerable attention. In this work an experimental program is used to determine the effect of high temperature on the interfacial bond shear modulus between concrete and reinforcement. Steel bars of different diameters were embedded in concrete cylinders for a depth less than that required for total development to assure failure by loss of bond. Specimens were then kept in an oven for different time durations and different temperatures. Specimens were then cooled by either keeping cylinders at room temperature or immersing them in water. The pull-out test was applied, and loads and displacements were recorded. Results from the pull-out test were then used along with an analytical model to calculate the bond shear modulus. The analytical model is based on the physical representation of the pull-out test, assuming linear elastic behavior of both steel and concrete.