Root branching affects the mobilisation of root-reinforcement in direct shear

Gerrit Meijer, David Muir Wood, Jonathan A. Knappett, A. Glyn Bengough, Teng Liang

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

The contribution of roots to the mechanical behaviour of soil has typically only been studied for the ultimate limit state. In these approaches, roots are typically modelled as straight and unbranched structures. This approach overlooks the fact that roots may have to deform significantly to mobilise their strength, a process that will be influenced by root architecture effects such as branching, amongst others. Sequential mobilisation of roots affects the peak root-reinforcement, thus differences in mobilisation are important to consider when quantifying root-reinforcement. In this paper, the effect of root branching was modelled using a large-deformation Euler-Bernoulli beam-spring model. The effect of soil was incorporated using non-linear springs, similar to p-y and t-z theory used for foundation piles. By connecting multiple beams together (i.e. applying appropriate linked boundary conditions at root connection points) the effect of branching could be analysed. A soil displacement profile corresponding with direct shear loading was then imposed and the response of the root analysed. It was shown that adding branches led to a quicker mobilisation of root-reinforcement. Branches increased the axial resistance to root displacement and changed the shape of the deformed roots. The presence of branching counteracted root slippage, and thus increased reinforcement. Larger branching densities increased this effect. This analysis demonstrated that the architecture of the root system has a strong effect on the mobilisation of root strength, which directly affects the maximum amount of reinforcement the roots will provide. Future modelling of root-reinforcement, both at the ultimate and serviceable limit state, should account for this effect.

Original languageEnglish
Title of host publication7th International Symposium on Deformation Characteristics of Geomaterials, IS-Glasgow 2019
EditorsErdin Ibraim, Alessandro Tarantino
PublisherEDP Sciences
Number of pages6
Volume92 (2019)
ISBN (Electronic)9782759890644
DOIs
Publication statusPublished - 25 Jun 2019

Publication series

NameE3S Web of Conferences
Volume92
ISSN (Print)2555-0403
ISSN (Electronic)2267-1242

ASJC Scopus subject areas

  • Environmental Science(all)
  • Energy(all)
  • Earth and Planetary Sciences(all)

Cite this

Meijer, G., Muir Wood, D., Knappett, J. A., Bengough, A. G., & Liang, T. (2019). Root branching affects the mobilisation of root-reinforcement in direct shear. In E. Ibraim, & A. Tarantino (Eds.), 7th International Symposium on Deformation Characteristics of Geomaterials, IS-Glasgow 2019 (Vol. 92 (2019)). [12010] (E3S Web of Conferences; Vol. 92). EDP Sciences. https://doi.org/10.1051/e3sconf/20199212010

Root branching affects the mobilisation of root-reinforcement in direct shear. / Meijer, Gerrit; Muir Wood, David; Knappett, Jonathan A.; Bengough, A. Glyn; Liang, Teng.

7th International Symposium on Deformation Characteristics of Geomaterials, IS-Glasgow 2019. ed. / Erdin Ibraim; Alessandro Tarantino. Vol. 92 (2019) EDP Sciences, 2019. 12010 (E3S Web of Conferences; Vol. 92).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Meijer, G, Muir Wood, D, Knappett, JA, Bengough, AG & Liang, T 2019, Root branching affects the mobilisation of root-reinforcement in direct shear. in E Ibraim & A Tarantino (eds), 7th International Symposium on Deformation Characteristics of Geomaterials, IS-Glasgow 2019. vol. 92 (2019), 12010, E3S Web of Conferences, vol. 92, EDP Sciences. https://doi.org/10.1051/e3sconf/20199212010
Meijer G, Muir Wood D, Knappett JA, Bengough AG, Liang T. Root branching affects the mobilisation of root-reinforcement in direct shear. In Ibraim E, Tarantino A, editors, 7th International Symposium on Deformation Characteristics of Geomaterials, IS-Glasgow 2019. Vol. 92 (2019). EDP Sciences. 2019. 12010. (E3S Web of Conferences). https://doi.org/10.1051/e3sconf/20199212010
Meijer, Gerrit ; Muir Wood, David ; Knappett, Jonathan A. ; Bengough, A. Glyn ; Liang, Teng. / Root branching affects the mobilisation of root-reinforcement in direct shear. 7th International Symposium on Deformation Characteristics of Geomaterials, IS-Glasgow 2019. editor / Erdin Ibraim ; Alessandro Tarantino. Vol. 92 (2019) EDP Sciences, 2019. (E3S Web of Conferences).
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