%0 Journal Article %T 尖萼金丝桃根系对边坡土体抗剪强度的影响 %T Effects of Hypericum Perforatum Roots on Shear Strength of Slope Soil %A 薛海龙 %A 唐彪 %A 张竞元 %A 沈彦会 %A 许建新 %A 王莹 %A Xue Hailong %A Tang Biao %A Zhang Jingyuan %A Shen Yanhui %A Xu Jianxin %A Wang Ying %J 水土保持通报 %J 水土保持通报英文版 %@ 1000-288X %V 39 %N 3 %D 2019 %P 87-92 %K 尖萼金丝桃;根土复合体;抗拉强度;抗剪强度;黏聚力 %K Hypericum acmosepalum;root-soil composite systems;tensile strength;shear strength;cohesion force %X [目的]探讨根系单根抗拉拔强度对边坡土体抗剪强度的影响,定量分析根系对边坡土体抗剪强度的增强作用,为评价植物根系增强边坡土体抗剪切性能提供依据。[方法]以2 a生尖萼金丝桃根系及其组成的根土复合体为研究对象,分别进行室内单根拉拔试验和根土复合体剪切试验,获得根系的抗拉强度及根土复合体试样黏聚力值;在此基础上分析根系抗拉强度与根土复合体黏聚力值之间的关系。[结果]尖萼金丝桃根系抗拉强度与根系直径存在负向幂函数关系,相关性系数均大于0.92;根系拉拔位移、抗拉拔力均与根系直径呈正相关关系,拉拔位移与抗拉拔力之间也表现为显著正相关关系;抗拉强度与根系直径、拉拔位移、抗拉拔力两两之间均呈负相关关系;根土复合体的黏聚力相较于无根素土均有不同程度的增长,增幅达17.25%~94.76%,黏聚力、黏聚力增长率均与根土面积比、根土体积比呈正相关关系。[结论]尖萼金丝桃根系拉拔特征对边坡土体抗剪强度产生显著的影响,边坡土体抗剪切性能评价指标与根系拉拔特征变化密切相关。 %X [Objective] The effects of single root pulling strength on the shear strength of slope soil were investigated, and the effect of root on the shear strength of slope soil was quantitatively analyzed in order to provide a basis for evaluating the shear strength of slope soil strengthened by plant roots.[Methods] The root-soil complex of 2-year-old Hypericum acmosepalum was studied. The indoor single-strand pull test and the root-soil composite shear test were conducted to obtain the tensile strength of the root system. The relationship between the root tensile strength and the cohesion force of the root-soil composite was analyzed.[Results] There was a negative power function relationship between the tensile strength and root diameter of H. acmosepalum, and the correlation coefficient was greater than 0.92. The root pullout displacement and tensile force were positively correlated with root diameter, and there was also a significant positive correlation between the pullout displacement and tensile force. The tensile strength was negatively correlated with root diameter, the pullout displacement and the pullout force, and the cohesive force of the root-soil composite increased by 17.25%~94.76%, compared with that of the rootless soil. The cohesion and cohesion growth rates were positively correlated with root-soil area ratio and root-soil volume ratio.[Conclusion] The pullout characteristics of the H. acmosepalum root have a significant influence on the shear strength of the slope soil, and the evaluation indexes of the shear resistance of the slope soil are closely related to the changes of the root pullout characteristics. %R 10.13961/j.cnki.stbctb.2019.03.015 %U http://stbctb.alljournal.com.cn/stbctb/home %1 JIS Version 3.0.0