[1]XU Wenxiu,YANG Ling,BAO Yuhai,et al.Tensile Mechanical Properties Single Root of Two Typical Flood-Tolerant Herbs in the Reservoir Riparian Zone[J].Research of Soil and Water Conservation,2020,27(05):259-264,272.
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Research of Soil and Water Conservation[ISSN 1005-3409/CN 61-1272/P] Volume:
27
Number of periods:
2020 05
Page number:
259-264,272
Column:
目次
Public date:
2020-08-20
- Title:
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Tensile Mechanical Properties Single Root of Two Typical Flood-Tolerant Herbs in the Reservoir Riparian Zone
- Author(s):
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XU Wenxiu1,2,3, YANG Ling1,4, BAO Yuhai1, WEI Jie2,3, LI Jinlin1,4, CAO Lingxin2
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(1.Key Laboratory of Mountain Surface Processes and Ecological Regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China; 2.School of Geography and Tourism, Chongqing Normal University, Chongqing 401331, China; 3.Chongqing Key Laboratory of Surface Process and Environment Remote Sensing in the Three Gorges Reservoir Area, Chongqing 401331, China; 4.University of Chinese Academy of Sciences, Beijing 100049, China)
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- Keywords:
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herbs; soil consolidation and slope protection; tensile force of single root; stress-strain characteristics of single root; reservoir riparian zone
- CLC:
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Q947.6; S781.25
- DOI:
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- Abstract:
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To further explore the mechanics mechanism of herb species roots on soil reinforcement and slope protection in the reservoir riparian zone, the mechanical properties of single root tensile of two typical herbs on soil reinforcement and slope protection were studied. The typical herbs(i. e. Cynodon dactylon and Xanthium sibiricum), which were widely grown in the reservoir riparian zone, were selected as the samples of study. Under the condition of different root diameter levels, the mechanical properties of single root tensile(i. e. tensile force, tensile strength, limit extensile rate and elastic modulus)of two herbs in the reservoir riparian zone were measured via single root tensile test. Furthermore, the stress-strain characteristics of single root during the tensile process were further analyzed. The results showed that:(1)the average value of single root tensile force data of Cynodon dactylon was larger than that of Xanthium sibiricum; under the condition of 0.30~0.50 mm and 0.90~1.00 mm root diameter levels, the single root tensile forces of Cynodon dactylon were significantly 28.06% and 9.95% larger than those of Xanthium sibiricum, respectively (p<0.05);(2)the average value of single root tensile strength data of Cynodon dactylon was 1.08 times that of Xanthium sibiricum; under the condition of 0.40~0.50 mm and 0.90~1.00 mm root diameter levels, the single root tensile strengths of Cynodon dactylon were significantly 24.10% and 18.72% larger than those of Xanthium sibiricum, respectively(p<0.05);(3)with the increase of root diameter, the single root tensile force of two herbs significantly increased, and the single root tensile strength the significantly decreased. These relationships can both be well fitted by power function;(4)the stress-strain characteristics of single root of two herbs showed the characteristics of elastoplastic materials, and the stress-strain curves for two herbs could be divided into four stages: elastic deformation, elastic-plastic deformation, strain hardening and fracture failure; the ultimate tensile stress in the elastic deformation stage accounted for about 50%~70% of the ultimate tensile strength;(5)the single root limit extensile rate of Cynodon dactylon was significantly higher than that of Xanthium sibiricum(p<0.05), and the single root limit extensile rates of Cynodon dactylon and Xanthium sibiricum were(23.59±0.44)% and(14.54±0.38)%, respectively; on the contrary, the single root elastic modulus of Cynodon dactylon was significantly lower than that of Xanthium sibiricum(p<0.05), and the single root elastic moduli of Cynodon dactylon and Xanthium sibiricum were(474.79±13.82)MPa and(540.77±14.21)MPa, respectively; the single root tensile mechanical properties of herbs are closely related to plant types and root diameter. On the whole, the single root tensile force and the single root tensile strength of Cynodon dactylon are both greater than those of Xanthium sibiricum. The ability to resist external stretching of Cynodon dactylon single root is stronger than that of Xanthium sibiricum, suggexting that Cynodon dactylon has stronger ability of soil reinforcement and slope protection.