Simulation of Root-Reinforcement Effect in Natural Slopes Based on Progressive Failure in Soil-Root Interaction

Author(s):  
Ram Chandra Tiwari
2014 ◽  
Vol 60 (No. 4) ◽  
pp. 166-173 ◽  
Author(s):  
E. Abdi

Vegetation significantly affects hillslope mechanical properties related to shallow landslides and slope stability. The objective of this study was to investigate and quantify the effect of Oriental beech root reinforcement on slope stability. A part of Hyrcanian forest in northern Iran was selected for the study area. To do the research, the Wu model (WM) was used and data related to the distribution and tensile strength of Oriental beech roots were collected. Root distribution was assessed using the concept of the root area ratio and trenching method. Laboratory tensile tests were conducted on fresh roots for strength characteristics. The factor of safety was calculated for two different soil thicknesses (1 and 2 m) and slope gradients between 10 and 45&deg;. The results showed that the root distribution generally decreased with increasing soil depth and the mean root strength value was 38.23 &plusmn; 1.19 MPa for 0.35&ndash;5.60 mm diameter range. The results verified a power relationship between tensile strength and root diameter. The reinforcement effect (C<sub>r</sub>) decreased with depth and the strongest reinforcement effect was in the second soil layer (10&ndash;20 cm) which showed a shear strength increase of 1.47 kPa. The increased factor of safety due to the presence of roots in one- and two-metre soil thicknesses was 27&ndash;44% and 15&ndash;26%, respectively. The improvement effect of roots was increased with increasing slope gradient and shallower soil thicknesses. &nbsp; &nbsp;


2015 ◽  
Vol 73 ◽  
pp. 216-219
Author(s):  
Yu Wang ◽  
Zongying Shu ◽  
Yingren Zheng ◽  
Shengxie Xiao

2012 ◽  
Vol 209-211 ◽  
pp. 1177-1182
Author(s):  
Xiao Ming Zhang ◽  
Qian Jin Liu ◽  
Xing Xiu Yu

Peanut root of crop lands in Menglianggu watershed in the upper reaches of Yi River were classified into different diameter classes by root diameter. The results show that (1) the relationship between force of pullout or breaking and root diameter is approximately linearity, and more significant linear for the latter; (2) Laboratory tests confirm the presence of a threshold or range of root diameter. When the diameter within the range (1.80-3.01mm), both root breaking and pullout occurred; when the diameter above 3.01mm, all roots broke under applied stress. While below 1.80mm, only roots were pulled out under applied stress. Root-soil resistance characteristic and root reinforcement effect were analyzed for different root classes: (3) pull out force of root-soil resistance is stronger than that of single root of the same root classes with the range from 6.03% to 39.39%.


2021 ◽  
Vol 13 (7) ◽  
pp. 3991
Author(s):  
Jeongjun Park ◽  
Indae Kim ◽  
Jeong-Ku Kang

This study investigated the effect of vegetation plant roots on the stability of the cover slopes of solid waste landfills. A large direct shear test and a root tensile strength test were conducted to quantify the effect of rooted soil of revegetation plants on the increment in shear strength of the soil as a method to protect the cover slope of solid waste landfills. In the large direct shear test, an increase in the shear strength of the ground with the presence of roots was observed, and the root reinforcement proposed in the literature was modified and proposed by analyzing the correlation between the root diameter and the tensile strength according to water content. The stability of the slope revegetation of a landfill facility, considering the root reinforcement effect of revegetation, was calculated by conducting a slope stability analysis reflecting the unsaturated seepage analysis of rainfall conditions for various analysis conditions, such as the gradient, the degree of compactness, the thickness of the cover, and the rooted soil depth of the landfill facility.


2021 ◽  
Vol 2021 ◽  
pp. 1-18
Author(s):  
Hao Bai ◽  
Ruidong Li ◽  
Wubin Wang ◽  
Kang Xie ◽  
Xiang Wang

The behavior of root-soil system has raised more and more attention in both ecological and geotechnical fields. In this study, a two-dimensional discrete element method is employed using PFC2D to simulate the root-reinforced soil. The root system is mimicked by chains of bonded discs, while the soil is modeled by granular particles. The tensile strength of the root is modeled by interdiscs’ bonding strength. Three laboratory tests were studied to calibrate the micromechanical parameters of DEM. Finally, direct shear tests on rooted soil are simulated to investigate the influence of different root characteristics on the root reinforcement effect.


1974 ◽  
Vol 11 (1) ◽  
pp. 89-108 ◽  
Author(s):  
G. Lefebvre ◽  
P. La Rochelle

Detailed investigations have been made on the sites of two landslides which occurred in the sensitive Champlain clay deposits of the Saint-Laurent Lowlands. Laboratory tests made on specimens cut from block samples have led to a better understanding and evaluation of the brittle behavior of these cemented clays. The results have shown that very little strain is required for the strength to decrease from a well defined peak value to a residual value; this brittle behavior is evident only when tests are made at sufficiently low stress level such that the cementation bonds are preserved during consolidation.The analyses of the slides have shown that the use of the peak strength parameters led to a gross overestimate of the factors of safety; the residual strength parameters, however, give a fairly accurate assessment of the stability, the calculated factors of safety being close to unity. That behavior may be explained by the fact that the cemented clay is extremely brittle and, like any other strain softening material, is subjected to the mechanism of progressive failure. This study leads to a very efficient practical approach to the analysis of the stability of natural slopes.


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