Experimental Study On Permeability And Root-soil Interaction Of Taproot Slope Soil

With the continuous promotion of ecological slope protection technology in the field of highway slope protection,the question of root-soil interaction has been taken seriously.Existing studies suggest that mainly by the root-soil interaction of plants can we achieve the purpose of a stable slope.For the existing of plants can affect soil permeability,and rainwater infiltration is also a major factor in causing geological disasters such as collapses,landslides and debris flows,so,it is controversial that whether the plant can play a good role in stabilizing the slope in the rainfall conditions.Based on the previous research results,the effect of rainfall on the steady slope effect of taproot system was studied by experiment,and through the analysis to provide a reasonable explanation for the dispute.Firstly,the effect of straight root plant type on the soil permeability of slope was studied by double-loop water injection test.The results show that taproot system can increase the soil permeability.At the same time,the soil infiltration decreased with the decrease of slope height.Secondly,the effect of soil water content on the soil-fixing effect of taproot system was studied by outdoor whole taproot pull-out test.The results show that in the range of any height,with the increase of soil water content,the whole root pull-out resistance increased firstly and then decreased.The greater the depth or the diameter of the root,the stronger the pull-out resistance of whole root.Finally,the effect of soil water content on the soil-fixing effect of taproot system was studied by indoor single taproot pull-out test.The results show that the single taproot pull-out resistive force increased with the increase of stress on the root surface and gradually became stable;with the increase of soil water content,the root pull-out resistance increased firstly and then decreased.By comparing the results of the outdoor whole taproot pull-out test and the indoor single taproot pull-out test,we can know that root-soil interaction contributes greatly to the pull-out resistance of whole root.