Plant and Soil

, Volume 324, Issue 1–2, pp 57–69 | Cite as

Effect of soil moisture content on the deformation behaviour of root-reinforced soils subjected to shear

  • Chia-Cheng Fan
  • Chih-Feng Su
Regular Article


This paper presents an experimental study on how soil moisture content affects the deformation behaviour within root-reinforced soils subjected to shear. In-situ shear tests were carried out in this research. The plant used in the shear tests was Prickly Sesban (Sesbania cannabina Merr.). The shear deformation within the root-reinforced soil after shear was measured. The effect of soil moisture content and the root area ratio on the development of the shear zone was investigated. The experimental results showed that the deformed shape within the soil for root-reinforced soils subjected to shear correlated well with the exponential decay function. The width of the shear zone of root-reinforced soils increases with increasing soil moisture content. Additionally, the width of the shear zone increases with increasing root area ratio. Widths of the shear zone developed in front of and beside the root structure are greater than those behind the root structure. Finally, the mechanism between the shear strength increase provided by roots and the development of the shear zone width are discussed in this paper.


Rooted soils Water content In-situ shear tests Width of shear zone Shear strength 



This research work was sponsored by the National Science Council in Taiwan under the grant number NSC 95-2221-E-327 -014. This support is gratefully acknowledged.


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Copyright information

© Springer Science+Business Media B.V. 2008

Authors and Affiliations

  1. 1.Dept. of Construction Engrg.National Kaohsiung First University of Science and TechnologyKaohsiungR.O.C.
  2. 2.Dali Engineering Consultant Inc., National Kaohsiung First University of Science and TechnologyKaohsiungR.O.C.

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