林木根系的加筋作用试验研究

Experiment on Forest Roots Reinforcement Mechanism

为探索林木根系的固土机理,基于加筋理论,采用三轴压缩试验的方法,对黄土加根土与素黄土在相同的土壤含水量和密度条件下,进行了25,50,75,100 kPa下的压缩试验,得出了加根黄土与素黄土的应力应变关系和应力差强度包线图,对加根土与未加根土的应力圆进行了分析,推导了加根土的"似黏聚力"。试验表明:在不同围压下,应变达到一定程度,含根土总是比素黄土的主应力差大一个值,说明在根系分布的不同深度,根系都增强了土体的强度。

With reinforcement theory,an experiment of different confining pressures on root-soil composite and plain soil roots under the same conditions of soil water content and density was carried out by using triaxial test. Four confining pressures of 25,50,75 and 100 kPa were tested. Based on the experiment results,a relationship of stress and strain between root-soil composite and plain soil as well as stress difference Mohrc＇s envelope is established. Further, pseudo cohesion of root-soil composite is deduced after analysis of stress difference Mohrc＇s envelope of root-soil composite and plain soil. The experiment shows the result that root-soil composite always have greater principal stress than plain soil by a value of when strain reachifig a certain extent under various confining pressures,which means roots at various soil depth can increase shearstrength of soils.