不同根系方位及径级下草本植物根土复合体抗剪强度试验研究

Experimental Study on Shear Strength of Herbal Root-soil Composites under Different Root Angle and Diameters

选取中国过渡带北侧山地土壤与莎草科植物(针薹草)开展植物根-土复合体抗剪强度试验研究,分析不同根系方位及径级下草本植物根-土复合体抗剪强度增强作用以及抗剪强度指标变化规律。试验结果表明:相同法向应力下,根-土复合体试样的抗剪强度随着方位角度的增大而逐渐增加,且当方位角θ=90°时即垂直布根时,根-土复合体试样的抗剪强度达到最大;根-土复合体试样的抗剪强度随着径级的增加而逐渐增大;随着根系方位角的增加,根-土复合体试样的黏聚力逐渐增大;相同方位角时,随着根系径级的增加,根-土复合体试样的黏聚力亦逐渐增大;根-土复合体内摩擦角与根系径级和方位影响不大且规律性不明显。

By taking the soil and sedge family plants in the north side of north-south transition zone of China as the research object,the shear strength of herbal root-soil composites were researched.The strengthening effects of the herbal root-soil composites and the variation of shear strength index were analyzed by using laboratory test.The results show that the shear strength of root-soil composites increased with the root angle increasing under the same conditions.When the roots were vertically distributed,the study found that the shear strength of root-soil composites was the highest.The shear strength of root-soil composites increased with the root diameter increasing.The cohesion of root-soil composites increased with the root angle and root diameter increasing.The friction angle of root-soil composites exhibits almost no variation with root angle and diameters increasing.