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| Titel |
Computational slope stability experiments implementing root system morphology in a generic hillslope environment |
| VerfasserIn |
Elmar Schmaltz, Martin Mergili, Stefan Steger, Thomas Glade |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250138962
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| Publikation (Nr.) |
 EGU/EGU2017-2112.pdf |
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| Zusammenfassung |
| Albeit tree root systems are capable to reinforce soils on hillslopes and hold the potential to
increase slope stability, the influence of root systems is often disregarded in physically-based
slope stability models. In this study, we intend to improve the parameterisation of root
reinforcement by analysing the effects of various root system types on slope stability in a
fully quantitative way. Therefore, we apply the 2.5D-slip surface model r.slope.stability to 23
root system scenarios imposed on a pyramidoid-shaped generic landscape. Shallow and
taproot systems, as well as a mixture of both are approximated with paraboloids. Different
stand and patch densities are considered for several stand compositions. The slope failure
probability (Pf) is derived for each raster cell of the generic landscape. Thereby,
internal friction angle and soil cohesion are varied within a given space of parameter
values. Pf is defined as the fraction of parameter combinations yielding a factor
of safety <1. Root reinforcement is considered through a constant root cohesion
imposed on all root systems. Average and standard deviation of Pf are analysed for
each scenario. As expected, r.slope.stability yields the highest values of Pf for the
scenario without roots. In contrast, homogeneous stands with taproot or mixed root
systems provide the lowest Pf. Generally, Pf decreases with increasing stand density,
whereby stand density appears to exert a more pronounced influence on Pf than patch
density. For patchy stands, Pf increases with a decreasing size of the tested slip
surfaces. The patterns provided by the computational experiments are largely in
accordance with the results of previous studies and in-field observations. The findings of
this study will be used to develop strategies towards appropriately parameterising
2.5D-slipsurface models to estimate root reinforcement in real-world case studies. |
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