摘要
采用直剪仪对杨柴（Hedysarum fruticosum）重塑的根-土复合体及素土进行不同法向荷载下的剪切试验,研究根-土复合体在土壤含水量,布根数量,根系直径以及变形速率梯度条件下的剪切特性,讨论法向应力,布根数量,根系直径,土壤含水率及剪切速率等对根-土复合体抗剪特性的影响。结果表明,在0.8m左右的浅土层内,根-土复合体提高土体抗剪强度的效果显著,根-土复合体粘聚力显著增大的情况下抗剪强度呈明显增大趋势,根-土复合体抗剪强度相对于素土的增长率为14%,粘聚力的增长率为17%,粘聚力的增加对复合体抗剪强度的提高起到显著的作用。杨柴在12.5kPa垂直荷载对应的0.8m的浅土层,当土壤含水率在12.5%∽16.5%,布根数量4∽6根,根系直径在1∽2mm径级范围,土壤孔隙水承压条件下,根系提高土体抗剪强度的有效性达到最佳范围。
Based on the direct shear apparatus for Hedysarum fruticosurn remodeling root and soil composite, and the shear test under different normal loads was conducted, studied the root and soil composite＇s shear properties under the condition that soil water content, root number, root diameter, and deformation velocity gradient and the effect that the normal stress, the root number, root diameter, the soil moisture content and shear rate on the root and soil composite shear characteristics was discussed, to reveal the root solid soil ero sion resistance mechanism. Around 0.8 m, according to the results in the soil, it was remarkable that the effect that root and soil composite improve the soil shear strength, the significant increased in root and soil composite cohesive force, composite shear strength was significantly increasing trend, composite soil shear strength relative to the prime growth rate was 14%, the shear strength of cohesive force of the growth rate was 17%, the increase of the cohesive force played a significant role on the composite shear strength enhancement. Hedysarum fruticosum under the vertical load of 12.5 kPa, when soil moisture content in 12.5%-16.5%, the number of root was 4--6, root diameter at level 1--2 mm diameter, under the condition of soil pore water pressure, the plant roots to improve the effectiveness of shear strength of soil was the best.
出处
《水土保持学报》
CSCD
北大核心
2014年第4期72-77,共6页
Journal of Soil and Water Conservation
基金
国家自然科学基金项目(41161046)
关键词
根-土复合体
抗剪强度
粘聚力
内摩擦角
root-soil composite
shear strength
cohesion~ internal friction angle
作者简介
格日乐（1970-），女，蒙古族，博士，副教授，主要从事水土保持与荒漠化防治研究。E—mail：gerile81@sohu．com
通讯作者：左志严（1992-），男，蒙古族，硕士，主要从事水土保持与荒漠化防治研究。Email：496117499@qq．com
