The Bending Mechanical Properties Of Four Kinds Of Plants Straight Root And Lateral Root Branch

Based on cantilever beam test,this paper researches on the bending mechanical characteristics of 3-4a plants:Salix psammophila,Caragana microphylla, Artemisia sphae-rocephala and Hippophae rhamnoides of straight root and lateral root branch.The results are as follows:(1) The bending force of four kinds of straight root and lateral root branch have a positive correlation of powerfunction with the diameter, The bending strength with the diameter have a trend of Polynomial relationship. The bending force and the bending strength average of straight root and lateral root of four kinds of plants comparead, Salix psammophila (18.57Mpa,16.31Mpa)> Caragana microphylla (14.48Mpa, 12.00Mpa)>Artemisia sphaerocephala (7.84Mpa,6.88Mpa)>Hippophae rhamnoides (4.34Mpa,3.56Mpa). Four kinds of plant lateral root branch bending force and bending strength are smaller than their straight root bending force and bending strength.(2) Different growth period has significant effects on the bending strength of each plant. The bending force and the bending strength of Salix psammophila, Caragana microphylla, Artemisia sphaerocephalas straight root and lateral root branch in early growing period is greater than the exuberant growing period. The bending force and the bending strength of Hippophae rhamnoides straight root and lateral root branch in exuberant growing period is greater than the early growing period.(3) Different soil moisture content has significant effects on the bending strength of each plant. Salix psammophila root in the drought soil environment will be better able to resist bending deformation, Caragana microphylla, Artemisia sphaerocephalas and Hippophae rhamnoides roots in the moist soil environment will be better to resist bending deformation.The bending force and bending strength of straight root and lateral root branch of Salix psammophila, Caragana microphylla, Hippophae rhamnoides has a trend of the first increase then in lower with the increase of soil moisture content.The bending force and bending strength of straight root and lateral root branch of Artemisia sphaerocephala has a growing trend with the increase of soil moisture content.(4) Different loading speed has significant effects on the bending strength of each plant in the same diameter. The influence of loading speed on straight root and lateral root branch bending strength varies due to plant, there is no consistent pattern.Within range of 1.5-2mm diameter class, The bending force and bending strength of straight root of 4 kinds of plant has a trend of the first increase then in lower with the increase of load speed; The bending force and bending strength of lateral root branch of 4 kinds of pant is reduced and then growing with the increase of load speed. Within range of 4.5-5mm diameter class, the bending force and bending strength of straight root of Caragana microphylla and Artemisia sphaerocephala has a growing trend with the increase of load speed.Salix psammophila straight root has a decreased trend with the increase of load speed; the trend of Hippophae rhamnoides straight root is reduced and then growing with the increase of load speed.The bending force and bending strength of lateral root branch of Salix psammophila and Caragana microphylla has a trend of the first increase then in lower with the increase of load speed; Artemisia sphaerocephala lateral root branch has a decreased trend with the increase of load speed; but Hippophae rhamnoides lateral root branch has a growing trend with the increase of load speed.