光纖光柵感測器於FRP結構應變量測之應用昱

Application of Fiber Bragg Grating Sensor in FRP Structural Strain Measurements

本研究主要探討光纖光柵感測器（FBG）應用於復合材料（FRP）的結構以及樹脂的硬化過程監測。文中先闡述了光纖光柵感測器的工作原理，再以光纖光柵感測器安裝於等向性金屬表面、複合材料（FRP）表面與FBG內埋入複合材料等三組試片，進行材料試驗，藉由FBG波長的變化來計算試片所受的應變。另一方面對樹脂硬化過程進行監測，藉由紀錄光波長變化，觀察樹脂成型時的溫度與內部應力的變化情形。最後對試片進行材料試驗與有限元素模擬驗證光纖光柵感測器的準確性。 In this study, we applied the fiber Bragg grating (FBG) sensors on monitoring the structural health of composite materials (FRP) and the resin curing process. At first the working principle of FBG sensors are introduced. Then to verify the accuracy of FBG measurement, the FBG sensor is installed on the isotropic metal surface, composite materials (FRP) surface and also embedded in composite materials to measure the change of FBG wavelength and consequently the strain of specimens. The agreement is good when the results compared to that measured by the strain gage and by FEM computation. In addition, the FBG sensor is combined with the thermocouple to monitor the strain and temperature changes during the VARTM molding processes. Then the residual strain after the molding process can also be obtained. Finally the measuring capability for FBG sensor embedded in FRP composite structural is verified by the numerical results of FEM analysis.