Highway Slope Protection Mechanics Analysis

A great deal of excavation is very common in the expressway construction. The excavation destroys the former vegetation and leads to many bare soil or rock slopes. Then the serious soil erosion comes into being and the balance of ecology environment is broken. Slope protection with vegetation is a kind of new technology which is used to stabilize rock slopes and beautify the ecological environment at the same time. Its theory is that vegetation can contain water and pinned up the soil. It's a comprehensive engineering technology that is involved geotechnical engineering, resumptive bionomics and botany etc. Research on the mechanical effect that the plant roots system influence slope can be used to analyze shallow stability of slope. Also it can provide theory foundation for the selection of plant varieties and virescence modes.Under the background of the actual project of expressway slope virescence in Jinan, Shandong province and contraposing the vacancy of research on the mechanical effect of slope protection with vegetation in our country at present, the dissertation tries to set up academic computational model of interaction between roots and soil, establish reinforced effect formula of roots, and study the superficial erosion of rocky slope on this basis.Based on the exploration and sampling on the spot and with plenty of direct shear tests, it can be concluded that the roots can enhance the ability of resist shear strength of soil. Selecting distribution density of roots as influence factors, the extent of cohesion of soil being enhanced is determined; the reinforced effect formula of roots is deduced.Contraposing the rocky slope after virescence, the critical condition of erosive failure on the surface is studied. The effect of distribution density of roots on the edaphic ability to resist erosion is studied on the basis of the reinforced effect formula of roots, and a system of estimate and forecast theedaphic ability to resist erosion including amount of roots is established, which can provide academic evidence for the selection of variety and quantity of grass seeds in the design of rocky slope biologic protection.