Long period fiber grating transverse load effect-based sensor for asphalt pavement pressure field measurements

From the angle of sensitivity of the LPFG resonant transmission spectrum, we demonstrate the sensitivity of LPFG resonance peak amplitude changing with transverse load and its direction correlation. The design of a miniaturized resonant peak modulation-based LPFG asphalt pavement pressure sensor is described. The compactness and simplicity of the device are achieved using the corresponding package obtained from common available asphalt. It is shown numerically that the sensor response has good regularity for a wide range of travel (15.3–76.5 kg). In the load range, the transmission rate of LPFG constantly enhanced and the resonant peak amplitude decreased from 14.154 dB to 13.672 dB which showed a good correspondence with loads. Linearity, travel and sensitivity are experimentally determined by different divider pressure ratios. A design chart that includes the travel (15.3–76.5 kg) and the sensitivity (7.8758 × 10−3 dB/kg) is finally proposed.