Measurement Accuracy Analysis of Distributed Fiber Optic Sensors for Asphalt Mixture Based on the DEM-FDM Coupled Method

Table 6

Calculation of the strain coefficient of DFOS.

Theoretical strain (μm/m)	Measured Rayleigh’s shift of the DFOS (GHz)
	1	2	3	Mean
338.983	−39.152	−36.594	−38.562	−38.103
677.966	−79.864	−77.523	−79.864	−79.084
1016.949	−122.659	−122.048	−124.437	−123.048
1355.932	−165.871	−170.497	−170.568	−168.978
1694.915	−216.153	−215.425	−216.915	−216.164
2033.898	−252.783	−258.972	−261.143	−257.633
2372.881	−296.444	−300.435	−305.824	−300.901
Strain coefficient (μm/m·GHz)	−8.04	−7.94	−7.86	−7.95