Abstract: Different fiber gratings have different center wavelengths. Many center wavelength optical signals can be transmitted simultaneously through only one optical fiber cable by the wavelength division multiplexing (WDM) technology of optical communication. The center wavelength fiber Bragg grating sensors are cascaded on the same optical fiber cable to comprise a linear array topological structure of sensors, hence, the quasi distributed measurement of multiple points could be achieved. This technology is rarely applied to the temperature monitoring of mass  concrete in China. We accumulated useful experiences and acquired valuable data by temperature controlling and measuring for the towers of the ship elevator of Three Gorges Project through fiber Bragg grating system.  

Key words: wavelength division multiplexing(WDM), fiber Bragg grating(FBG), array, center wavelength, ship elevator, temperature controlling and monitoring