浅层滑坡中乔木直根阻滑效应及变形特性的试验研究--平行双根

Experimental Study of Effect of Slide Resistance and Deformation of Tree's Tap Root in Shallow Landslide——Parallel Double Root

为探索乔木根系在浅层滑坡中的阻滑效应及变形特性,以自行设计加工的大型层叠式根土复合体直剪仪为基础,对海口地区橡胶树(乔木)直根进行了不同深度剪切面处的乔木根土复合体大型直剪试验,得到了不同剪切面处乔木根系的阻滑能力及变形特性。试验结果表明:对比相同推力作用下含根土和素土剪切盒位移,发现根系的存在具有提高土体强度,延缓破坏的能力,乔木根系的存在主要通过根土之间的摩擦力起到对土体的加筋作用来有效提高土体的强度。随着剪切深度的增大,根系的阻滑能力逐渐加大;但加筋率逐渐减小。靠近剪切面处的根系相对位移最大,随着距剪切面距离的增加根系位移逐渐减小。根系的变形说明根系有将剪切面上下土体连成整体共同承受剪力的作用,且根系变形越大抵抗抗剪强度的能力越大。研究成果对于深入研究乔木直根在浅层滑坡中的阻滑及变形机理提供了试验依据,为更好的将植被根系的阻滑作用运用到浅层边坡治理中奠定了基础。

In order to explore the slide resistance effect and deformation of tree's tap roots in shallow landslide,on the basis of big cascading complex root soil direct shear apparatus design by myself,it has been conducted the large-scale direct shear text of rubber tree's root-soil complex at different depth that the tree lived in Haikou area,obtained the effect of slide resistance and deformation of tree's tap root to soil at different shear depth. Test results show that the presence of root system has the ability to improve the strength of soil to delay the damage by comparing the displacement of root-soil and soil with the same thrust and the existence of tree root system can effectively improve the strength of the soil mainly through the friction between soil and tree root system,With the increase of shear plane depth,the root's resistance increases gradually,but the reinforcement ratio of root were decreased. The displacement of root near the shear plane were bigger than the others,and the root displacement decreased gradually with the increase of distance from the shear plane. Deformation of the root show that the root system has the function of connecting the upper and lower soil of the shear plane into the whole together to bearshear force and the greater the root deformation,the greater the resistance to shear strength. The research results for further study of effect of slide resistance and deformation mechanism of tree's tap root in shallow landslide provided experimental basis.