Numerical analysis of matric suction effects of tree roots

Publisher:
Thomas Telford Ltd.
Publication Type:
Journal Article
Citation:
Proceedings of Institution of Civil Engineers, Geote..., 2006, 159 (2), pp. 77 - 90
Issue Date:
2006-01
Full metadata record
Files in This Item:
Filename Description Size
Thumbnail2008007528OK.pdf476.52 kB
Adobe PDF
The use of native vegetation in the coastal regions of Australia has become increasingly popular for stabilising railway corridors built over expansive clays and compressive soft soils. The tree roots provide three tabilising functions: (a) they reinforce the soil; (b) they issipate excess pore pressures; and (c) they establish sufficient matric suction to increase the shear strength. The matric suction generated within the tree root zone propagates radially into the soil matrix, as a function of the moisture content change. Considering soil conditions, the type of vegetation and atmospheric conditions, a mathematical model for the rate of root water uptake is developed. A conical shape is considered to represent the geometry of the tree root zone. Based on this model for the rate of root water uptake, the pore water pressure distribution and the movement of the ground adjacent to the tree are numerically analysed. Field measurements taken from the previously published literature are compared with the authors' numerical predictions. It is found that, given the approximation of the assumed model parameters, the agreement between the predicted results and field data is still promising. The study indicates that native vegetation improves the shear strength of the soil by increasing the matric suction, and also curtails soil movements.
Please use this identifier to cite or link to this item: