Temperature-Based Design Method for Concrete Cone Failure Under Fire Conditions

This paper introduces a temperature-based design method for determining the tensile concrete cone capacity of anchors subjected to fire exposure. Current prescriptive approaches, most notably Eurocode 2, rely solely on embedment depth and fire duration for fire exposure from one or more directions on one concrete face with and without edge effects. The purpose of this work is to develop a temperature-based design method for predicting tensile concrete cone failure of anchors under fire conditions. Through an experimental program, this study demonstrates that anchor capacity can be conservatively described by temperature associated with embedment depth. A parametric analysis on the influence of concrete strength, anchor group effect, edge effect, concrete cracking, anchor type and heating orientation on different concrete faces defines the scope of application of the design method. The proposed method incorporates measured temperature profiles, offering a more precise alternative to the existing design method in Eurocode 2 and enabling flexible design for different structural configurations and fire scenarios. Optimized design is enabled in comparison to the existing prescriptive method (EN 1992-4) exclusively based on embedment depth and fire duration. Research findings demonstrate that anchor capacity correlates strongly with the temperature at the effective embedment depth under varying conditions.