Loading...

Stability Analysis of Slopes with Inclusion of Hydrological and Vegetation Effects

Emadi Tafti, Mohsen | 2020

210 Viewed
  1. Type of Document: Ph.D. Dissertation
  2. Language: Farsi
  3. Document No: 55494 (09)
  4. University: Sharif University of Technology
  5. Department: Civil Engineering
  6. Advisor(s): Ataie Ashtiani, Behzad
  7. Abstract:
  8. Landslide is a natural hazard associated with economic losses and fatalities. The geometric of the slope, the soil properties, hydrological factors, and groundwater are important factors that affect the stability of a slope. The landslide investigation is important due to the identification and prevention of damages. Thus, more researchers studies on this subject. The new questions in this field are “how can simulate the vegetation effects in slope stability analysis?” and “what effects do precipitation and infiltration have on landslide triggering?”. Although the classic methods of slope stability analysis provide the initial information for the design, they have limitations in answering new questions. Some available commercial programs have made good progress in numerical modeling of the hydrodynamics of porous media, but there are still limitations in vegetation cover modeling and related hydrological factors. Therefore, there is a need to develop an integrated model that able to modeling vegetation cover and hydrological factors. Moreover, the weather condition, special topography, and the high potential to landslides in Iran increase the importance of the investigation on an integrated model.Accordingly, in this study, it is developed a numerical model that consider vegetation impacts and hydrological factors effects simultaneously on slope stability analysis. This physically-based model combines the soil hydrology and slope stability analysis and can simulate the effect of change in pore water pressure due to rainfall infiltration on slope stability. Also, the impact of vegetation cover on hydrology and stability modules consider simultaneously. The vegetation canopy intercepts precipitation, increases the surcharge load, and transmits the wind force to the soil. Besides, the roots of vegetation extract water, reinforce the soil, and increase the permeability of the soil.In the following, the developed model is used for a case study in the Kheyrud forest in northern Iran. In this section, the mechanical effects of vegetation have been assessed in the stability of the slopes. The analysis demonstrated that considering the mechanical features of vegetation can be improved safety factor up to 22%. The increase in the stabilization role of vegetation by reducing soil strength was one of the interesting results of the analyses. The sensitivity analysis was also performed in this case study. The results showed that the ratio of the root zone to the surface soil thickness is the most important parameter on the contribution of vegetation on slope stability. In other words, it has resulted that the vegetation can be effective in shallow landslides, whereas, in deep landslides the stabilization role of vegetation is limited
  9. Keywords:
  10. Numerical Modeling ; Vegetation ; Landslide ; Hydrological Modeling ; Slope Stability ; Root Reinforcement

 Digital Object List

 Bookmark

...see more