University of Natural Resources and Life Sciences, Vienna (BOKU) - Research portal
Gewählte Doctoral Thesis:
Barbara Maria Switala
(2016):
Analysis of Slope Stabilization by Soil Bioengineering Methods.
Doctoral Thesis - Institut für Geotechnik (IGT),
BOKU-Universität für Bodenkultur,
pp 2012.
UB BOKU
obvsg
FullText
- Abstract:
- In recent years, soil bioengineering methods have gained popularity as fully ecological and economical solutions to slope stabilisation. Soil bioengineering measures can be effectively used in combination with geosynthetics or conventional slope protection. This work aims to introduce a new model for the mechanical root reinforcement which is combined with a model for the root water uptake. A new model for root reinforcement is developed based on the Modified Cam-clay model for unsaturated conditions. A thermodynamically consistent, mathematical formulation is obtained by introducing a new constitutive parameter. This allows the evolution of the failure surface with the degree of root reinforcement. The model is implemented in the two finite element codes, namely: Comes-Geo and Abaqus. Root water uptake is defined as a volumetric sink term in the flow continuity equation. This concept is extended to slopes with different root architectures, and combined with the mechanical model. With this numerical model, we study a stability of various vegetated slopes (in 2D and 3D), subjected to rainfall. Numerical calculations are carried out for different root geometries, rainfall intensities, and plant distributions. The effect of plants on slope stability is studied by comparing the numerical results of the barren slope with vegetated slopes. The numerical results show that presence of vegetation can have a significant influence on the overall stability of slopes. The water uptake by plant roots reduces the moisture content and gives rise to increased soil suction which adds to the soil strength. As a consequence, the instability of slope is delayed by the presence of plants. Our numerical model offers an efficient tool to study the mechanical and hydrological effect of plants on rainfall-induced slope failures.
- Betreuer: Wu Wei
- 1. Berater: Florineth Florin