香根草根系固土拉力的原位测定

 应用锚杆拉力计和项目组自行设计改进的剪切箱，原位测定了不同深度（10cm，20cm）分蘖期香根草根系固土、单根拉力。结果表明，在给香根草施加载荷初期，根系都会发生弹性形变，荷载与位移都按比例增加，呈现一定的线性关系。当载荷超过根系抗拉极限后，随着拉力的继续增加，根系发生塑性形变，载荷与位移关系逐渐偏离直线，反映出非线性弹性特征，测定的土体样方与土体分离。但与裸土样方相比，在施加同样载荷的情况下，有根样方位移明显要小于无根样方，说明香根草具有一定的固土能力，并且根系入土越深，植物固土能力越强。

Research on In situ Measurement for Soil Fixing Capability of Vetiver Roots

The field experiment of in situ measuring soil fixing capability by vetiver (Vetiveria zizanoides) in 10cm and 20cm depth with the anchor shank tensiometer and self designed shear box were conducted. The results showed that vetiver roots at tillering stage elastically deformed with small load, and the displacement increased with the increasing of load, and showed a liner relationship. When the load exceeded the maximum tensile strength of roots, the plastic deformation would occur. Load and displacement gradually deviated from linear relationship which showed the nonlinear elastic characteristics and sampling soil square breakdown from bulk soil finally. Compared with bare soil, the displacement of soil with vetiver was shorter under the same load, as showed the soil fixing capability of vetiver grass. Soil fixing capability of vetiver increased with root penetrating from 10 to 20cm.