Fig. 1. Diagram of settlement monitoring system based on weak fiber grating technology

Fig. 2. Settlement fitting diagrams of WFBG static levels. (a) Settlement fitting diagram of No. 1 WFBG static level; (b) settlement fitting diagram of No. 2 WFBG static level

Fig. 3. Temperature and strain characteristic curves of strain sensing optical cables. (a) Temperature characteristic curve; (b) strain characteristic curve

Fig. 4. Relationship between mean response and load and fitting curves of embedded optical cable forward and reverse stroke. (a) Relationship between wavelength and load; (b) fitted curve

Fig. 5. WFBG static level and strain sensing optical cable layout diagram

Fig. 6. Settlement of GIS pipeline support piers

Fig. 7. Transverse surface displacement