Abstract:
Abstract: There exist a number of slope deformation monitoring methods, but as for most of methods, only the surface deformation can be used to measure slope, while in the practical engineering the slope internal deformation is very important to determine the sliding surface of a slope. Although the slope internal deformation can be monitored by means of few technologies, it is very difficult to arrange and maintain these sensors. Also, the existing slope internal deformation sensors are easily influenced by extreme harsh environment, and the arrangement of equipment is not convenient for the internal deformation monitoring. In this study, slope deformation monitoring system was combined with smart magnetic rock and full tensor magnetic gradiometer. Accordingly, the simplified algorithm of magnetic survey was given for slope deformation monitoring method based on the magnetic gradient tensor and magnetic dipole, and consequently, the three dimensional positions of smart magnetic rock can be obtained in real time. Through the displacement change of smart magnetic rock in the deep internal position of slope, the sliding process and instability of slope can be evaluated. The thrust load was crucial for slope sliding when the slope sliding was the driving force type or caused by the load on the slope top. Therefore, the physical model test by driving force was used as landslide simulation system to verify the slope internal deformation monitoring system by means of smart magnetic rock and full tensor magnetic gradiometer. The landslide simulation system was established by aluminum alloy model box, separated jack and force sensor, and the sliding of slope was realized by applying driving force at the back of slope. The results showed that when the driving force was 2 500 N, there existed the turning on the curve of driving force versus critical points' horizontal displacements measured by soft film size. When the driving force was ranged from 2 500 to 3 100 N, six critical points' horizontal displacements increased drastically with instability failure of slope. With regard to the smart magnetic rock, there also existed the turnings on the curve of the relative distances from smart magnetic rock to reference points and smart magnetic rock's horizontal displacements versus driving force. And then both the relative distances from smart magnetic rock to reference points and smart magnetic rock's horizontal displacements changed sharply. It showed that the slope deformation development and slope instability evaluation can be judged by relative distances from smart magnetic rock to reference points and smart magnetic rock's horizontal displacements, and the results were in accord with the monitoring assessment by soft film size, which can be used as reference in the further study and practical engineering monitoring. It also showed that the simplified algorithm of magnetic survey for three dimensional positions of smart magnetic rock and slope internal monitoring were effective and useful. And it was suggested that the magnetic interaction of smart magnetic rocks should be studied in order that the smart magnetic rock network can be established for slope internal deformation monitoring in the practical engineering.