Due to increasing industrial settlements in cities and consequently increasing the industrial waste produced by the industry, we should find ways to use this waste or destroy them. The industrial city of birjand, having many factories and industries such as tile industries, PVC pipes, plastic containers, rubber and …, as well as a development that is done every day, manufactured industrials waste materials in a large amount. The purpose of this research is survey industry and industrial waste accordingly and after examine this material can added them as a additional materials. As a result they have been used to improve soil properties and a way to get rid of these materials will be available. In this study the resistant parameters of reinforced soil has been study. Reinforced soil has been obtained by add a kind of plastic waste made from polystyrene and polypropylene in to a sandy soil of the special area of birjand city. Three different forms of polypropylene were used to add to soil. Type A in form of lens. Type B in form of tube and powder polypropylene or type C. Purpose of this study is evaluated resistance parameters of reinforced soil such as friction angle and cohesion. Consequently nomination the best waste material and the optimum percent for reinforced the oil. In this tudy direct hear test and compression test has een used. Has been observed that the use of this material decreases the maximum dry density and increase the amount of optimum moisture content. Increasing percent of polystyrene, increase resistance and increase the friction angle. On the other hand use of higher percentage of polystyrene will be effective on the cohesion. No increase in resistance of reinforced soil with using polypropylene in type A and C was observed. In almost all case the soil friction angle is improve. Process of friction angle on polypropylene type B and C have a decrease trend but in the propylene type A dos not view this case. Use all type of polypropylene in amount of one percent has the best effect on the cohesion Key Words Reinforced Soil, Polystyrene, Polypropylene, Sandy Soil, Strength Characterization
