Inversion analysis of the shear strength parameters for a high loess slope in the limit state

• Published in: Journal of mountain science 2021, Vol.18 (1), p.252-264
• Main Authors: Lin, Xiao-yan, Zhang, Lin-fan, Yang, Ze, Li, Ping, Li, Tong-lu
• Format: Article
• Language: English
• Subjects: Analysis; Earth and Environmental Science; Earth Sciences; Ecology; Environment; Geography; Height; Internal friction; Landslides; Limit states; Loess; Original Article; Parameters; Physical properties; Shear strength; Slope; Slope stability; Slopes; Soil; Stability analysis
• ISSN: 1672-6316; 1993-0321; 1008-2786
• DOI: 10.1007/s11629-020-6142-z

It is difficult to obtain reliable shear strength parameters for the stability analysis and evaluation of high loess slopes. Hence, this paper determines slope elements and physical parameter of 79 slopes with heights of [40, 120] m based on the measured loess slopes in the Ganquan and Tonghuang subregions of northern Shaanxi Province, China. In the limit state of the loess slope (stability factor F s is 1.0), a fitting equation for the slope height and width is established. Then, the model is developed by stability analysis software-SLOPE/W, and the comprehensive shear strength parameters corresponding to different slope heights of the high slope in the study area are obtained by inversion using the Morgenstern-Price method. The results show that when the height of the slope increases, the cohesion c increases in the soil, and the internal friction angle φ decreases. This change is consistent with the characteristics reflected in the composition and physical properties of the slopes, and the comprehensive strength parametric curves are very similar between the Ganquan subregion and the Tonghuang subregion. A landslide that occurred in Miaodian-zaitou of Jingyang County, Shaanxi Province, is selected to verify this inversion method, and the results show that the calculated shear strength parameters of the inversion are consistent with the measured value of the actual slope.