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FBG sensors have excellent compatibility with CFRP sheets. It can be embedded into CFRP sheets to fabricate the “smart” CFRP. This paper conducted 4 pieces of CFRP-strengthened RC beams, and embedded FBG sensors and strain gauges on the steel, concrete and CFRP of RC beams. The simulation program of flexural load effects of RC beams is compiled based on the theory of reinforced concrete and ANSYS. The experimental results show that during the load bearing process: the compatibility is perfect between FBG sensor and CFRP; the linear relationship of FBG sensor and strain gauge is uniform; the numerical simulation results and the measuring results of strains of tensile steel and compressive concrete, the load agree well. So utilizing the smart CFRP strengthened RC structures can realize the dual function of advanced rehabilitation and real-time health monitor and evaluation.

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Fiber-reinforced resin-based plastics are widely used in structural composites for aerospace and automotive applications, and they often face extreme load conditions in actual working environments. It is challenging to monitor the damage of the structure during the vibration process. This study was aimed at using buckypaper (BP) sensors to monitor the structural health status of composite structures under ambient vibrations. First, the feasibility of flexible printed circuit instead of wire is verified by the tensile experiment. Then the vibration monitoring experiment of the composite cantilever beam is carried out by using BP sensors systematically. The sweep frequency experiment determines the excitation frequency of the cantilever beam. Low-period vibration fatigue cycle and high-period vibration fatigue cycle experiments are designed to verify the vibration monitoring method using BP sensors. Besides, the signal response of BP sensors in the vibration experiment is analyzed, and the relationship between ΔR/R 0 and vibration acceleration is obtained. Finally, through the change law of ΔR/R 0 of the sensor, the cumulative damage caused by vibration fatigue is visualized. It is demonstrated that the monitoring method based on BP sensors can be applied to study the damage behavior of composite structure under the vibration environment.