Research On Road Property Of Flexible Cement Concrete Composite Pavement

Based on the analysis of the conflict between special application environment and environment protection, riding comfort, fireproofing security, durability in highway pavement, this paper adopts complex modified technique of cement concrete to explore a low elastic modulus and high toughness flexible cement concrete (FCC) pavement materials. According to the properties of FCC and the stress of pavement structure, a new type of pavement-Flexible cement concrete composite pavement (PCC-FCC) is introduced, which the Portland Cement Concrete(PCC) is used in the lower layer and Flexible Cement Concrete (FCC) is used in the upper layer. Different materials are used in different layers of pavement structure, in order to satisfy different needs. This pavement not only have common cement concrete pavement advantages in construction, fireproofing security, durability, but also a equivalent riding comfort of flexible pavement materials. First, the way for FCC mix is discussed. In this studied, the lightweight aggregate, waste tire rubber particles and polymer are used. An orthogonal experimental method is adopted to optimize the mix proportion, in order to decrease the elastic modulus on the premise of necessary strength. Next, through contrast experiment, the road properties of FCC (such as strength, rigidity, impact resistance, abrasion resistance, dry shrinkage) are discussed. Then the microstructure and modified mechanism also are studied. Finally, with the help of finite element method, the load stress and thermal stress in the PCC-FCC composite pavement is studied. The results indicate that PCC-FCC showed a good meet to pavement application need.