生态环境学报Issue(4)：631-637,7.DOI:10.16258/j.cnki.1674-5906.2015.04.013
高速公路不同植物防护边坡根土复合体抗剪能力研究
Research on the Root-soil Composite Anti-shearing Strength on Expressway Slope in Different Plant Protection Measures
摘要
Abstract
With the slope of the first section at Yuexi part of Yuexi-Wuhan Expressway as the research object, the home-made direct shear apparatus was used to conduct in-situ measurement of the anti-shearing strength of plain soil and root-soil composite under the growing periods of 61, 95 and 125 days respectively, at the same time, physical model prediction has also been done, and in this way, quantitative evaluation of the time effects of soil reinforcement by the plant root system. The test shows that, (1) Under different growing periods, the plant root systems could all significantly increase the anti-shearing strength slope topsoil, and the enhancement presented a positive correlation with the growth time of plants. Among them, the root system with a growing period of 120 days had the biggest increase in its anti-shearing strength, with an enhancement of 5.21 kPa. (2) During the shear failure process of soil mass, the root system can effectively improve the performance of resistance to deformation of slope surface. The plain soil sample reached the peak value of shear strength with a displacement of around 18 mm, and for the root-soil composite, this number was 19~40 mm; in addition, the average residual shear strength of root-soil composite is 2.68 times of that of plain soil. (3) By comparing the field measured value with the value calculated with Wu Model, Wu Model overestimated the increase of soil’s shear strength by the root systems. For this issue, related scholars have proposed a reduction factor of 0.4 or 0.56, but it still fails to be consistent with the measured value. Through calculation, a correction factor of 0.47 was introduced, and the accuracy of model prediction has increased by 6.92%, which can help more accurately evaluate the slope stabilization effects by the plant root system.关键词
根土复合体/生长期/抗剪强度/模型预测Key words
root-soil composite/growing period/anti-shearing strength/model prediction分类
资源环境引用本文复制引用
刘治兴,杨建英,杨阳,许泽宁,马亚云,黄琴焕..高速公路不同植物防护边坡根土复合体抗剪能力研究[J].生态环境学报,2015,(4):631-637,7.基金项目
安徽省交通科技项目 （）
