Method for determining the position of landslide slip-surface with a typical inclinometric curves

• Published in: Journal of mountain science 2024-02, Vol.21 (2), p.413-432
• Main Authors: Chen, Hao, Wu, Hong-gang
• Format: Article
• Language: English
• Subjects: Acceleration; Clustering; Depth; Earth and Environmental Science; Earth Sciences; Ecology; Environment; Geography; Identification methods; Inflection points; Interpolation; Landslides; Monitoring; Original Article; Position (location); Sliding; Slip; Slumping
• ISSN: 1672-6316; 1993-0321; 1008-2786
• DOI: 10.1007/s11629-023-8044-3

In the actual monitoring of deep hole displacement, the identification of slip surfaces is primarily based on abrupt changes observed in the inclinometric curve. In conventional identification methods, inclinometric curves exhibiting indications of sliding can be categorized into three types: B-type, D-type, and r-type. The position of the slip surface is typically determined by identifying the depth corresponding to the point of maximum displacement mutation. However, this method is sensitive to the interval of measurement points and the observation scale of the coordinate axes and suffers from unclear sliding surfaces and uncertain values. Based on the variation characteristics of these diagonal curves, we classified the landslide into three components: the sliding body, the sliding interval, and the immobile body. Moreover, three different generalization models were established to analyze the relationships between the curve form and the slip surface location based on different physical indicators such as displacement rate, relative displacement, and acceleration. The results show that the displacement rate curves of an r-type slope exhibit a clustering feature in the sliding interval, and by solving for the depth of discrete points within the step phase, it is possible to determine the location of the slip surface. On the other hand, D-type slopes have inflection points in the relative displacement curve located at the slip surface. The acceleration curves of B-type slopes exhibit clustering characteristics during the sliding interval, while the scattered acceleration data demonstrate wandering characteristics. Consequently, the slip surface location can be revealed by solving the depth corresponding to the maximum acceleration with cubic spline interpolation. The approach proposed in this paper was applied to the monitoring data of a landslide in Yunnan Province, China. The results indicate that our approach can accurately identify the slip surface location and enable computability of its position, thereby enhancing applicability and reliability of the deep-hole displacement monitoring data.