Page - 982 - in Book of Full Papers - Symposium Hydro Engineering

For instance, the probability of FOS more than 5 is about 20% in slope without vegetation, yet, that is more than 90% in slope with vegetation. This is a substantial increase. Based on PDF diagrams, the amount of mFOS and σFOS are ascertained for both with and without vegetation system. Using these values, the reliability indexes against instability are as Table 2. There is a significant increase in the reliability index. Table 2. Reliability index for both systems System mFOS σFOS 𝜷 Without vegetation 2.841 2.027 0.907 With vegetation 8.372 1.440 5.166 Considering geotechnical uncertainty, the aim of this paper is to investigate the reliability of relationship between vegetation and slope stability in order to assess its benefits. A probabilistic analysis approach (Monte Carlo method) based on limit equilibrium employing Python programming was developed using random samples for each parameter generated. The overall results indicate that vegetation roots have a considerable stabilizing effect on the slope, limited to the rooting depth. It is appeared that through a matrix of tensile fibers, enhanced soil cohesion has a significant effect on slope stabilizing and the shallower the location of the sliding plane, the bigger the impact of vegetation. REFERENCES 1. Whitlow R (2001) Basic Soil Mechanics. Prentice Hall, 2. Freer R (1991) Bio-engineering: the use of vegetation in civil engineering. Construction and Building Materials 5 (1):23-26 3. Baecher GB, Christian JT (2005) Reliability and statistics in geotechnical engineering. John Wiley & Sons, 4. Fell R, Hartford D Landslide risk assessment. In: Landslide risk assessment, Proceedings of the international workshop on landslide risk assessment, edited by: Cruden, D. and Fell, 1997. pp 51-110 5. Horrey P, Grocott G Quantitative Risk Assessment Methods for Determining Slope Instability Risk. In: Engineering and Development in Hazardous Terrain: New Zealand Geotechnical Society 2001 Symposium, Christchurch, August 2001, 2001. Institution of Professional Engineers New Zealand, p 119 6. Danjon F, Barker DH, Drexhage M, Stokes A (2007) Using three-dimensional plant root architecture in models of shallow-slope stability. Annals of Botany 101 (8):1281-1293 7. Hytiris N, Fraser M, Mickovski SB (2015) Enhancing slope stability with vegetation. International Journal of GEOMATE 9:1477-1482 8. Coppin NJ, Richards IG (1990) Use of vegetation in civil engineering. Construction Industry Research and Information Association London 9. Wu TH (2007) Root reinforcement: analyses and experiments. Eco-and ground bio-engineering: the use of vegetation to improve slope stability:21-30 982