Landslide Monitoring Suitability of Sensor-Enabled Piezoelectric Geocables Based on Drawing Tests

Early warning of landslides is an important topic in geotechnical engineering health monitoring and disaster risk assessment. However, there is currently a lack of low-cost and distributed methods for measuring the internal deformation of slope soil over a wide area. Piezoelectric materials are widely used in various high-precision sensors because of their piezoelectric and impedance-strain effects. Hence, in this study, a sensor-enabled piezoelectric geocable (SPGC) with a polyvinylidene fluoride (PVDF) piezoelectric material was used as the core, and drawing tests of the SPGC under different normal stresses $\sigma _{n}$ and drawing rates ${V}_{d}$ were conducted, including pull-out and pull-off tests. The results demonstrate that as an intelligent geosynthetic, the tensile strength of SPGC can reach 53.6 MPa, and the strain measurement range can reach 7.71%. The normalized impedance ${k}_{Z\,}$ –drawing displacement ${D}_{d}$ curves corresponded well with the drawing force ${F}_{d\,}$ –drawing displacement curves (the development of pull-out and pull-off can be detected). The force-normalized impedance curves can be described using a linear model. The real-time voltage ${U}_{\text {(real-time)}}$ of the pull-out and pull-off tests increased with an increase in the normal stress and drawing rate. Therefore, the proposed SPGC sensing material provides a potential new method for soil disaster location, precursor recognition, and graded early warning.