Computational analysis of composite landslide thrust considering spatial differences in parameters

Due to the variability of the values of the same geotechnical calculation parameters in different landslide zones of composite landslides, it exacerbates the difficulty of discerning the size of landslide thrust. According to the damage mode of composite landslide, the geological model of landslide was constructed by generalization, on the basis of which the physio-mechanical model of the landslide was established, and the parameters of each zone were analyzed theoretically. According to the characteristics of landslide destabilization and the previous research work on the division of composite landslide evolution stages, the landslide evolution process was divided into five stages: front and back fissure cracking, front and back slip zone local softening, front and back slip zone expansion, central slip zone softening, and overall slope destabilization. The landslide thrust calculation formula under different evolution stages was constructed based on the transfer coefficient method and static equilibrium conditions. By taking a composite landslide of Han-Banan Railway as an example, it revealed the change rule of landslide thrust with the increase of horizontal distance, and compared and analyzed the calculation results with the calculation results derived from the numerical differences of the same geotechnical calculation parameters without considering different slip zones. The results show that: (1) when calculating the composite landslide thrust, by considering the influence of the difference in the value of the same geotechnical calculation parameter in different slip zones, the calculation results are more accurate and problems such as irrationality of the calculated thrust due to a single value can be avoided. (2) according to the different evolution stages of composite landslide under the change rule of thrust, in the early stage of landslide, the pushed area and traction area should be primarily reinforced. When the central locking area begins to slide, the central locking area should be mainly reinforced; meanwhile, the pushed area and the traction area should also be reinforced. (3) On the basis of identifying the evolution stage of composite landslide, the spatial change rule of thrust is derived from the calculation formula of landslide thrust constructed in this stage so as to put forward more reasonable prevention and control measures. © 2024, Central South University Press. All rights reserved.