Vegetation concrete (VC) laid as a reinforcement base and covered by a soil layer with vegetation has been increasingly used to beautify the landscape, reduce environmental pollution and control stormwater runoff. In this study, the effects of municipal solid waste (MSW) on vegetation characteristics of modified VC were tested under different mix compositions. We first explored the effects of the mixed concrete environment on Festuca elata and perennial Ryegrass for 60 days. Then, the influence of various MSW contents added to different percentages of cement on scouring resistance of VC was examined. The experimental results revealed that the germination rates and plant heights of both species decreased with the increase in concrete content. Considering the scouring resistances, the optimal mix proportion of MSW-modified VC was recommended as No. 25, with 5% KW fertilizer, 8% cement and 0.5% wheat straw in this study. Furthermore, adding a small amount of fallen leaves or silica fume to VC can promote the growth of both species to some extent, although these additions had an inverse effect on the scouring resistances. The results contribute to beneficial knowledge for future research on the feasibility of the use these species with VC technology for slope ecological restoration.

In the prevention of soil erosion, vegetation is an economical and environmentally friendly control methods, the most basic indicators of the plant protection design is solid soil function of plant roots. From the perspective of composite the fine rooted soil as a kind of special composite materials, the fine roots as the reinforcement material, using fracture mechanics theory the paper analyzes the enhancements and toughening effect of roots on the soil in order to illustrate the mechanism of solid soil and protection slope of plant roots. At different stages of loading the bridging effect of root has different manifestations, during the micro-crack propagation the bridging effect of root as follows: an equivalent closure role imposed on the expansion of micro-cracks, the stress concentration of micro-cracks cutting-edge can be passivated, the stress distribution more uniform, increasing the shear capacity of the soil; during the macro-crack propagation the bridging effect of root as follows: the roots across crack gradually pulled out to prevent cracking or crack propagation, crack propagation must consume a large amount of energy, thereby increasing the strength and toughness of the composite soil. Due to matrix cracking the load transferred to roots, by stress proliferation the load is passed to the soil surrounding roots. while its stress reached peak, soil had strain strengthening characteristics with the strength, toughness and plastic of composite soil having been greatly improved. Finally, it was verified by numerical simulation and laboratory test of the direct shear tests.