Functionality Study on Light-Weight Ecological Substrate

Abstract

Dry-sprayed ecological slope protection technology is an effective mean to restore the ecological environment of rock slope, which has been continuously studied and improved by scholars since its advent. Based on the existing research, a new type of dry-sprayed ecological substrate with carbon fiber and expanded polystyrene (EPS) particles was proposed to achieve lightweight and conductive heating. The ingredients of the ecological substrate are EPS, cement, carbon fiber, graphite powder, soil, water-retaining agent, and pH adjusting agent, respectively. In order to investigate the ecological performance and the physical properties of the substrate, the growth rule of Zoysiagrass was investigated by pot experiment and orthogonal range analysis, and the density and conductivity of the substrate were tested. The result shows that proper EPS particles in the substrate can improve soil structure and promote plant growth, and they play a similar role as soil conditioner. However, when the content of EPS particles exceeds 4%, the substrate is difficult to solidify by cement, which will lead to disintegration. EPS is the main factor affecting the germination and growth of plants, followed by cement, while carbon fiber and graphite powder content effect less. The optimum proportion for plant growth is EPS particle 4%, cement 2.5%, carbon fiber 1%, graphite powder 10%, pH adjusting agent 2.5%, and water retaining agent 0.1%. EPS particles can effectively reduce the density of the substrate and thus reduce weight. The average conductivity of the substrate specimens is 384 Ω·cm, which has great conductivity.