In order to monitor the strain of concrete caused by freeze-thaw (F-T) cycles, two novel types of white light interferometer (WLI) sensor are designed and tested. The first type of sensor is poured the whole saturated concrete cylinder which coiled optical fiber with epoxy for encapsulation, and the second type coat neutral silicone sealant on the surface of cylinder, where enwound with optical fiber only. Each of the type was conducted on two sensors, the sensor of the first type was named W-sensor, and the sensor of the second type was named S-sensor. The comparison of the two novel types of sensor was conducted based on the test results, and the test result showed that though all of the two types of sensor can monitor the variation of strain with the process of F-T cycles, however, the type of S-sensor is more stability and reasonable.
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