Deformation Evolution Law and Instability Criterion of Creeping Landslides

To address the difficulty for evaluating the stability of creeping landslides identified in displacement monitoring and warning, the numerical calculation model of soil slope is established by using the software FLAC^3D, and the surface displacement and inner stress evolution law of creeping landslides was analyzed based on the strength reduction method of FEM. As a result, the instability criterion of creeping landslides was established, which was then verified by laboratory experiment and applied to typical creeping landslide cases analysis. The results indicate that the internal failure characteristics of creeping landslides during the occurrence and development to slip failure can be reflected by landslide surface displacement. And the landslide surface displacement not only changes regularly with the degree of landslide failure, but also presents an abrupt inflection point when the landslide stability phase changes. The stability state of the landslide obtained from the instability criterion established based on the landslide displacement change law was in line with the actual condition, proving that such instability criterion is applicable to practical projects.