Calibration method of FBG sensor based on asphalt pavement indoor small size test

The study on the calibration method of FBG sensor used to measure strain of asphalt mixture is the precondition of FBG sensor application in asphalt pavement information monitoring. In this paper, monitoring results of indoor small size test process tested by traditional resistance strain gauge and FBG sensor are compared and analysed to complete FBG sensor calibration. The preparation process of three-layer composite rutting specimen buried with strain gauge and FBG sensor is studied based on the analysis of measuring principle of strain gauge and FBG sensor. The dynamic response in rutting test is monitored, by which, the regression relationship of monitoring results tested by two kinds of test elements is established. Based on three-point bending test of small beam, the tensile strain of beam bottom monitored by resistance strain gauge is compared with theoretical strain. Finally, the calibration equation of FBG sensor test results is established.