The Apply Of Iron Tailings As Subgrade Materials

The paper studies the iron tailings used as road base material and provides a new way for the comprehensive utilization of iron tailings.This paper combined with iron mine tailings as road base course material is proved by experiment. Adding the cement, biological coagulation enzymes as stabilizer of iron ore tailings. According to the national standard the unconfined compressive strength as the only evaluation index, the-optimum distribution of aggregate ratio is cement: gravel:iron tailings:biological condensing enzyme=5:30:68:2. In this mix, iron tailings as pavement base material strength can meet the national standard of Expressway and highway road use standard.In order to improve the service life and optimization of pavement materials, the inorganic combined with the addition of polypropylene fiber, and focus on improving the pavement material mechanical properties and durability properties. The experimental results show that: the splitting tensile strength increases with the addition of polypropylene fiber increased first and then decreased, when the fiber content is1.5kg/m3the splitting tensile strength reaches the maximum.Bending tensile strength with the addition of polypropylene fibers increased first and then decreased, when the fiber content is0.9kg/m3specimens, the flexural strength is the highest. The addition of polypropylene fiber can help reduce the modulus of resilience of test value, resilient modulus increases with the increase of polypropylene fiber.Adding different amount of polypropylene fiber has no influence on freeze stability.Adding different amount of polypropylene fiber has no influence on water stability. The anti scouring experiment show that the quality loss decreased first and then increased with the increasing of the fiber content, when the fiber content is1.5kg/m3, the specimen erosion rate dropped to the lowest. Fiber can effectively reduce the specimen shrinkage. According to the results, the optimal dosage of polypropylene fiber1.5kg/m3.The research results of this paper have some reference value for the promotion of iron tailings used as subgrade materials.