Experimental Study on Tensile Properties and Reinforcement Ability of Plant Roots

摘要

Plant roots have considerable impact on the soil shear resistance. To fully understand the mechanics of how plant roots reinforce soil stability, controlled laboratory test has been conducted on five kinds of pioneer plants that are generally applied to land restoration works. It aims to improve understanding of tensile material behaviour of roots, and proposes a more accurate procedure to calculate the effect of soil reinforcement. We selected five representative species (Alfalfa, Cynodon dactylon, Vetiver grass, Ryegrass and Indigofera amblyantha) of the ecological restoration projects as the pioneer plants of gentle slope in Mount Cuiping to examine these effects. Results of tensile tests showed that the differences of root tensile strength were significant among five species, and root tensile strength was mainly affected by several factors, such as shape, diameter, moisture and age. Curves of root tensile deformation displayed the whole process root endure under tensile stress. Combined with characters of strength and deformation, an evaluation model of soil reinforcement proposed in this paper was proved to be more rational by contrast test.