植被护坡中植物根系的阻裂增强机理研究

Research on Resistance Cracking and Enhancement Mechanism of Plant Root in Slope Protection by Vegetation

本文从复合材料的角度对植物根系的加固机理进行了分析,将含根系的岩土体看成一特殊的复合材料,其中岩土体为基体相材料,根系为增强相材料,根系犹如纤维,将对根土复合体起到阻裂增强作用.并运用能量原理对根系的阻裂增强作用进行了分析研究,得出根土复合体中某点的抗剪强度增量的计算公式及该点处根系的抗拔力和最大拔出长度的计算公式,得出某点抗剪强度增量主要与该点处根的面积比、面密度、长径比、抗拉强度、根土间的黏聚力及摩擦系数有关,及如果根系深入某点以下锚固段长度大于该点处的最大拔出长度,根系将被拉断的结论.

The paper analyzed the strengthening mechanism of plant root from the perspective of composite materials. The rock and soil with plant roots was regarded as a special composite material. The rock and soil was basal materials, and plant root was the reinforcement materials. Root like fiber played a cracking resistance and enhancement role in the composite of root and soil. By Using energy principle to study root＇s cracking resistance and enhancement action, a calculating formula of shear strength increment of one point in the composite of root and soil was educed, and the formulas of root＇s resistance pull-out risistance and maximum pull-out length in the point too. A theory is established that the shear strength increment of one point mainly relates to root＇s area ratio, areal density, the ratio of length and diameter, tensile strength and the cohesion and friction coefficient between the roots and soil. Thus the conclusion is drawn that if the anchor length of root deep into one point is greater than the maximum pull-out length of the root in the point , the root would break.