Mechanical Properties Research Of EPS Lightweight Soil Mixed By Polypropylene Fibers

With the rapid development of the economy, the construction industry in ourcountry accounts for an increasing higher proportion of GDP.As sustainabledevelopment trend is highly advocated,the construction industry is faced with thesame task of resource conservation and environmental protection. The properties anduse of the soil is the most important geotechnical studies. EPS lightweightpolypropylene fibers mixed soil breaks the traditional pattern of soil mechanicsstudies in the past.EPS lightweight polypropylene fiber mixed soil has many advantages, such aslightweight, high-strength, short construction period and so on, and also achieve thepurpose of environmental protection, which has been used as a lightweight filler. Thepolypropylene fiber, EPS and cement were mixed in different proportionsin clay tomake the specimen. Direct shear tests indoors, unconfined compressive strength testsand consolidated undrained triaxial tests were carried out. Preliminary studies of itsmechanical properties have been conducted below:(1)Through the density test we can achieve the amount of cement andpolypropylene fibers added to EPS lightweight soil mixture is less important. We canapproximately gain that the amount of EPS determines their density.(2)By Unconfined compressive strength tests, we can get the factors affecting theintensity of light soil mixture: EPS granules dosage, cement additive amount, theamount of polypropylene fibers added.(3)Through consolidated undrained triaxial tests and direct shear tests, we cananalyze the effects of addition of EPS particles, the amount of cement added,polypropylene fibers, confining pressure and normal stress and other factors on thedeformation characteristics of lightweight mixed soil. Lightweight mixed soilstress-strain curve has three characteristics: non-linear characteristics, strain softening,strain hardening characteristics. The damage value of the standard of EPS lightweightpolypropylene fiber mixed soil uses the maximum principal stress difference, whichmeets Mohr-Coulomb failure criterion. Each variable has an impact on the shearstrength parameters of the lightweight mixed soil. The shear strength envelope hastwo forms：Mansard and linear.(4)Lightweight mixed soil has shear failure, drum-shaped surface damage and nosignificant damage to the compacted form, which are mainly related to the confiningpressure and intensity of light soil sample itself.(5)By studying the methods of preparation and conservation of soil samples forEPS lightweight polypropylene fiber mixture, it can be considered that applying thistechnology to the specific reality of the project is feasible.