Theoretical Analysis And Experimental Study On Mechanical Behavior Of Reactive Powder Concrete Bridge Deck Pavement

Reactive Powder Concrete(RPC)has the characteristics of high strength,high toughness and excellent durability.RPC skid-resistance,RPC fatigue properties,RPC-NC(Normal Concrete)shear properties determine whether it can be applied on deck pavement.In this paper,based on the theory of material and mechanics,take the engineering example as the research background,developing a finite element modeling method for steel and concrete composite deck pavement,studying the effect of steel fiber content and surface treatment process on the surface skid resistance of RPC,researching the influence of steel fiber content on shear strength of RPC-NC specimen bonding surface,Studying the relation of RPC single compression fatigue properties and the steel fiber content.The theoretical analysis and experimental study of the mechanical properties of RPC in bridge deck pavement are of great significance for improving pavement performance and prolonging the service life of pavement.The main conclusions are as follows:(1)Based on the complexity of the structure of the self anchored composite beam suspension bridge,the structure is simplified and the beam-shell element model is established.The design parameters of the bridge deck under the most unfavorable load and its corresponding working conditions are obtained,and the solid model of the detail structure is further analyzed,and the stress states of the pavement material are obtained.(2)The increase of steel fiber content can effectively improve the skid-resistance of RPC surface.The friction coefficient of RPC can reach 0.38 and 0.46 when the steel fiber content of RPC is 1.5%and 3%.After the treatment of slotting,print and slotting-printed,the vertical and lateral skid-resistance properties of the surface are greatly improved.The measured results show that the surface treated RPC can meet the requirements of the relevant specifications for the skid-resistance of the cement concrete pavement.The surface longitudinal skid-resistance performance of the 3%steel fiber RPC with the slotting print composite treatment is the best,and the friction coefficient is 0.73.(3)The shear strength of RPC-NC adhesive surface increases to a certain extent with the increase of steel fiber content in RPC.The shear strength of the adhesive surface is 1.87MPa when the RPC steel fiber content is 3%,which meets the shear strength requirements of the stacked structure at the working stage.(4)Increasing the amount of steel fiber can improve the fatigue strength of RPC.The RPC with 0%,1.5%and 3%steel fibre content can meet the requirements of specification for fatigue performance of pavement cement concrete.Comparing with the reference group,the fatigue strength of RPC with 1.5%steel fiber content increased by 235.99%;the fatigue strength of RPC with 3%steel fiber content increased by 364.89%.The research results lay down the foundation for the application of RPC in the bridge deck pavement.