基于离散元模拟的草本植物根系分布对黏土抗剪强度的影响研究

Influence of herbal plant root distribution on soil consolidation capacity based on discrete element simulation

摘要:

为深入研究草本植物根系分布对土壤固土能力的影响。通过堆积试验对植物根系-土壤接触参数进行标定,利用EDEM离散元软件研究不同根系形状,根系长度,根系间距以及根系数量对土壤固土能力的影响。结果表明:根土复合体剪应力大于无根土体剪应力,植物根系对土壤有加固的作用,提高抗剪强度;均布形根系较于三角形根系,对根土复合体抗剪强度的提升更明显;根系长度越长,根土复合体剪应力越大,固土能力越强,200 mm的根系阻力最大值比150 mm的根系阻力最大值增加5.34%,150 mm根系阻力最大值比100 mm根系阻力最大值增加18.44%;当根系间距等于两根系最长根毛长度(两根系根毛不重叠)时,根系固土能力最强;一定数量范围内,植物根系数量越多,固土能力越好。

Abstract:

In order to fully understand the influence of herb root distribution on soil consolidation ability,the plant root-soil contact parameters were calibrated through accumulation tests.The EDEM discrete element software was used to study the effects of different root shapes,root lengths,root distances,and root coefficients on the soil-solidification capacity.The results showed that shear stress from root-soil composite was greater than that of unrooted soil.Plant roots could reinforce the soil and increase the shear strength.Compared to the triangular root system,the evenly distributed root system improved the shear strength of the root-soil complex more significantly.The longer the root system,the greater the shear stress of the root-soil complex,the stronger the soil-fixing ability.The maximum root resistance of 200mm was 5.34% higher than that of 150mm,and the maximum root resistance of 150mm was 18.44% higher than that of 100mm.When the root space equaled to to the longest root hair length of the two root systems (the root hairs of the two root systems did not overlap),the root system had the strongest soil-fixing ability;within a certain range,the more the plant root,the better the soil-fixing ability.