A Research On Mechanical Properties Of Root System Of Tropical Rainforest Species And Field Shear Experiment

This paper select Terminalia Mantaly,Khaya Senegalensis,Flamboyanttree and Chinese Bischopwood four arbor taproot species from Hainan tropical rainforest,which is using in a large field shear experiment by a self-made experiment device.In each root and soil in situ composite samples set up three different depth of the shear plane,access to the root and soil under different depth of complex relationship between shear stress and displacement curve.Through laboratory direct shear tests we get shear strength of undisturbed soil,Calculate the different root and soil complex soil shear strength growth rate by comparing their distribution.And analyzes the roots of the tree species geometry characteristics,the root area ratio on different soil depth and soil complex shear performance impact.Finally it is concluded that under the condition of the scene in situ,Terminalia Mantaly composite soil shear strength of the growth rate is Biggest,followed by is Chinese Bischopwood and Flamboyanttree,Khaya Senegalensis root is the worst.There is an optimal root soil area ratio,enables the root to maximize their own to improve the soil shear strength.A tensile Test and a shear test is conducted for four arbor species root.Through the experiment,we get the tensile performance of different tree species and different roots in the process of tensile stress-strain relationship,it is concluded that the root diameter,the diameter and the moisture content of three kinds of factors and the roots of the relationship between tensile properties,and we also get the root diameter of the influence law of the shear performance to the root.Based on the experiment,we discussed the root-composite soil shear strength of the increase and species single tensile resistance,shear resistance,learning the law of the performance.