3种生态护坡植物根固效应的试验研究

Root reinforcement effect of three ecological slope protection plants

为研究不同植物根系的固土护坡效果,对含根原状土和植物根系分别进行了三轴压缩试验和单根抗拉试验。采用函数拟合及有限元分析的方法,探讨了不同参数条件下草本植物根与土的强度特性。研究结果表明:(1)原状土的剪切过程均具有应变-硬化特征,抗剪强度指标与含根量间具有良好的相关关系;同一根系深度或相近含根量条件下,鸡眼草根土复合体的抗剪强度最大;(2)根径、根系深度与抗拉力学性能指标间呈现出极显著的相关关系;在根径或根系深度一定时,鸡眼草根系的极限应力与应变、弹性模量等较其它2种植物均具有显著优势、具有更强的抵抗变形能力;(3)在相近含根量、相同根系深度下,鸡眼草的边坡安全系数最高。研究成果可为太行山地区生态护坡植物物种的筛选提供参考,为生态边坡设计、浅层滑坡与水土流失的防治提供有力支撑。

This study aimed to examine the soil stabilization and slope protection effects of different plant roots.Triaxial compression tests were conducted on undisturbed soil samples containing roots,and single-root tensile tests were conducted on individual plant roots.The strength characteristics of herbaceous plant roots and soil under different parameter conditions were explored using function fitting and finite element analysis methods.The study findings were as follows:(1)the shear process of undisturbed soil exhibited strain-hardening characteristics,and a significant correlation was observed between the shear strength index and the root content.Among plant species with similar root depth or root content,the root-soil complex of Kummerowia striata demonstrated the highest shear strength.(2)A highly significant correlation was observed between root diameter and root depth with tensile mechanical performance indicators.When root diameter or root depth was kept constant,the root system of Kummerowia striata significantly outperformed the other two plants on the ultimate stress,strain and elastic modulus,suggesting a better deformation resistance.(3)Under similar root content and consistent root depth conditions,Kummerowia striata exhibited the highest slope safety coefficient.The results of this study can serve as a valuable reference for selecting plant species for ecological slope protection in the Taihang Mountains region and also provide strong support for ecological slope design,shallow landslide prevention,and soil erosion control.