Effect of Heat-Induced Chemical Degradation on the Residual Mechanical Properties of Ultrahigh-Performance Fiber-Reinforced Concrete

AbstractThis study investigates the effect of chemical degradation on the residual mechanical properties of ultrahigh performance fiber-reinforced concrete (UHPFRC) after temperature exposure ranging from 100 to 900°C. Emphasis has been placed on the isolation of chemical degradation. A long drying period and a slow heating rate were used to minimize the buildup of excessive pore pressure caused by water evaporation and transport constraints. To identify critical areas of chemical degradation, differential scanning calorimetry and thermo gravimetric analysis were performed. The results were used in correlation with existing research to aid in deriving a simplified model for predicting the temperature-dependent stress versus strain behavior of UHPFRC.

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