The Anti-tensile Mechanical Characteristics Of Three Kinds Of Self-cured Lateral-root Branch And Straight Root After Axial Damage

To clarify the soil reinforcement mechanisms by plant roots,selecting Caragana korshinskii,Salix psammophila and Hippophae rhamnides as object of this study.In the plant growth stage(May),The lateral root branch and straight root of the three plants within the scope of the 1.00 to 4.50 mm diameter were stretched by instantaneous axial force with the instrument of HG100,then the damaged roots were buried.After 3 months wound curing,the anti-tensile force of the test roots was measured.The results are as follows:(1)The survival rate of the lateral root branch and straight root under two levels of damage force(30%and 70%of anti-tensile force)were above 60%,The test root vigor were lower than that of the parallel contrast,The root diameter increased after wound curing.(2)After 3 mouths wound curing,The anti-tensile force of the lateral root branch and straight root of the three plants and the diameter are positively correlated with power function,and the anti-tensile strength and diameter are negatively correlated with a power function.The anti-tensile force and anti-tensile strength of three plants were decreased compared with the parallel contrast.When the damage force is 30%and 70%of anti-tensile force respectively,the anti-tensile strength descent rate of straight root after 3 mouths wound curing were:Caragana korshinskii(16.88%,21.14%)Salix psammophila(12.65%,21.83%),Hippophae rhamnides(26.86%,53.57%),the anti-tensile strength descent rate of lateral root branch after 3 mouths wound curing were:Caragana korshinskii(18.34%,30.97%),Salix psammophila(16.25%,29.17%),Hippophae rhamnides(34.9%,54.10%).The tensile strength of lateral branch were less than straight root with same root diameter after 3 months wound curing.The tensile strength of plant species as follows after 3 months wound curing:Caragana korshinskii>Salix psammophila>Hippophae rhamnides.(3)For Caragana korshinskii,Salix psammophila and Hippophae rhamnides,compared with the roots before curing,when damage force was 30%of anti-tensile force,The anti-tensile strength of three plant straight root increased 16.75%,30.37%and 12.11%.The anti-tensile strength of three plant lateral root branch increased 13.47%,33.27%and 7.28%.when damage force was 70%of anti-tensile force,The anti-tensile strength of three plant straight root increased 10.76%,16.68%and-28.84%.The anti-tensile strength of three plant lateral root branch icnreased-4.09%,12.71%and-24.37%.(4)The anti-tensile strength of the lateral root branch and straight root show:The anti-tensile strength under 30%of anti-tensile force less than that under 70%of anti-tensile force.Under the same degree of damage force,The anti-tensile strength after 3 months wound curing less than after 5 months wound curing.