Abstract:We take a landslide near Libi coal mine in Qinshui county, Shanxi province as an example to carry out high-precision deformation monitoring for almost one year. By constructing strain models under small deformation conditions and finite deformation conditions, we study the spatial and temporal characteristics of the deformation field of the target landslide at different stages before, during and after sliding. Through analysis of the maximum and minimum principal strain fields, we find that the retaining wall of Libi coal mine before anchor cable reinforcement still has about 40% inhibitory effect on the accelerated sliding of the early landslide front. The compressive impact between the landslide front and the retaining wall has obvious spatiotemporal inhomogeneity, that is, the direction and strength of principal compressive strain between them have obvious spatiotemporal variations. The local strong strain anomaly of the landslide may be a significant indicator of the structural failure of the monitoring target. The local strong tensile deformation at 830 m contour in the study area on December 13, 2020, has good correspondence with a transverse 10-20 cm wide cracking on the slope. Under the steady-state background where the overall migration and relative deformation of the landslide are small, the occurrence and development of cracks on the slope surface indicate that the failure and development of the landslide are still continuous. In the post-sliding adjustment stage, the deformation mode of the whole landslide, especially the trailing edge where sliding occurs, is quite complex, and it also experiences compression deformation and tension deformation with similar strength. The landslide, after 3 months, was not completely stable, and only a local sliding trend like the direction of the original main sliding axis was initially formed in the middle part of the trailing edge.
CAO Dongdong. Spatial and Temporal Characteristics of the Deformation Field of Landslide Mass Based on Displacements and Strain Fields[J]. jgg, 2023, 43(5): 498-504.