Experimental investigation of the mechanical properties of carbon fiber-reinforced polymer (CFRP) tendons during and after exposure to elevated temperatures

This paper presents test results on the tensile mechanical properties of carbon fiber-reinforced polymer (CFRP) tendons during and after high-temperature exposure. Detailed experiments are conducted to determine the failure strength and elastic modulus of 8-mm-diameter CFRP tendons. The test results indicate that the CFRP tendon stress-strain relationships remained almost linear during and after high-temperature exposure. The CFRP tendon failure strength and elastic modulus gradually decrease with increasing temperature. Further study reveals that the CFRP tendon mechanical properties greatly recover before 200 degrees C, which represents a possibility for the repair of concrete members strengthened with CFRP tendons after fire. These test data are utilized to establish CFRP tendon thermodynamic models. They can be applied in computer programs to model the behavior of concrete members strengthened with CFRP tendons during and after high-temperature exposure.