Anchorage and detailing of reinforcement under fire action

In recent years, an increasing attention was devoted to evaluating the effects of temperature exposure on the bond properties between a steel bar and the surrounding concrete, with a lower focus on the effects on bond length and, more in general, on the consistency among existing design models, when considering a fire scenario. The current paper proposes a unified approach for both cast-in and post-installed rebars to evaluate the effects of temperature exposure on bond length and reinforcement detailing in reinforced concrete members in bending subjected to a simulated fire event. Starting from a consistent evaluation of decay of bond properties as a function of temperature, different geometrical configurations of beam/slab to column/wall connections are considered. For a given fire duration, the impact on bond length is evaluated as a function of bar position and size, also focusing on the potential modifications in the overall load-transfer mechanism, when bond properties are excessively impaired.