Research Of Crumb Rubber Modified Cement Concrete Pavement Performance

Rubber powder modified cement concrete, which is characterized by low Young's modulus, large deformation and good crack resistance, become a research hotspot in various fields of engineering in recent years. Scrap tire rubber powder being mixed in cement concrete road improves the durability of concrete, on the other hand, expands areas of application of rubber powder, so rubber scrap turn into the green resources in the field of highway engineering from the black waste and environmental pollution, have huge significance of waste utilization and environmental protection.The effect on mechanical property and some performance on road of cement mortar and cement concrete were investigated respectively when additive composition of scrap tire powder replaces par of sand, included research projects on workability, pressive strength, rupture strength, shock resistance, contractibility, drying shrinkage, temperature shrinkage, carbonization and Chloride ion erosion performance in circumstances of marine atmosphere. Beside, microstructure,fracture pattern and hydrate products of rubber powder cement matrix were analyzed through Scanning electron microscopy(SEM), and analyzed and investigated the mechanism of the results of the study.Mechanical property testing indicates that the workability and flexural strengths of mortars and concretes were decreased by the addition of rubber powder, but the ratio of rupture strength and pressive strength is increased, it was said that the flexibility was improved. When the Rubber powder modified cement concrete was being done strengths test, it wouldn't be quickly broken like the ordinary concrete, and it could still keep in good shape that showed powerful crack resistance. Through used the dropping hammer impact testing recommend by the United States ACI-544 Committee, the result showed that the impact toughness has been greatly enhanced.SEM images of cement paste with rubber powder manifest that, micro-cracks and pore structure in cement mortar reduced gradually by the increase of the rubber powder contents, section had exposed some short fiber, it was favorable for improving crack resistance, shrinkage performance, corrosion resistance and impermeability of cement parent metal. But the bond interface region of rubber powder,short fiber and cement matrix was weak, it was negative impact on the strength of modificated cement mortar.In this paper, the research focus and innovation was a more systematic study on the shrinkage performance of the rubber powder modified cement concrete, and through simulated the Oceanic and Atmospheric Environment of Qin zhou Port in Guang Xi, tested the influence of the rubber powder on the cement concrete carbonation and chloride ion corrosion performance by chemical titration method, the result showed that the right amount of rubber powder can improve the self-cement mortar shrinkage, drying shrinkage and temperature contraction performance, and suitable amount of rubber powder can reduce cement concrete carbonation depth and chloride ion erosion depth.