Mesomechanics characteristics of soil reinforcement by plant roots

  • Yun-Yan ZhouEmail author
  • Xiao-Mei Wang
Original Paper


Vegetation for slope protection is widely used nowadays because of the role of plants in slope strengthening and environmental restoration. However, due to the lack of effective testing, root reinforcement in soil stability is mostly assessed in macroscopic mechanical analysis. This paper aims to investigate the mesomechanical characteristics of soil reinforcement with plant roots using a computed tomography (CT) triaxial compression apparatus. A series of unconsolidated-undrained CT triaxial compression tests of clay samples with and without Broussonetia papyrifera roots were conducted. By using CT technology, distinctive CT images and detailed CT data were obtained at different strains during loading. The soil crack data of CT images were then analyzed with MatLab. Finally, the evolution of internal structure of soil samples during loading was investigated. It indicated that the number, length, and width of cracks in the rooted soil samples evolved more slowly than those of the non-rooted samples during loading. In addition, it was observed that soil samples with thicker roots continued to bear loads even after local cracks appeared due to root bridging. In summary, at the mesoscopic level, the fact that roots inhibit further crack expansion and their bridging behavior helps increase the soil strength and toughness.


Soil reinforcement Plant roots Damage evolution Computed tomography (CT) Triaxial compression test 



Computed tomography




Standard deviation


Fine roots


Thick roots


One was fine root, the other thick root



This work was supported by the National Natural Science Foundation of China (No. 41102228) and Hubei Provincial Communications Department projects (No.2004056061). The authors would like to especially thank Changjiang River Scientific Research Institute of Changjiang Water Resources Commission for providing experiment field and test equipment. The authors would also like to thank Engineer Yongzhen Zuo for his CT scanning support.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Faculty of Engineering, China University of GeosciencesWuhanChina

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