| Steel box girder has become the main form of the long-span bridge construction in our country which has the advantages of light-weight, great ability of span, convenient erection etc. However, general asphalt-based materials has poor stability in the high temperature, poor adhesion of the steel plate, and extremely easy to produce the transposition and upheaval problem. Therefore, the research of steel bridge deck pavement materials has become one of the most focuses in the world. In this paper, for the requirement of flexibility, high temperature stability and cohesiveness to steel plate on Steel bridge deck pavement materials, Cement-Emulsified asphalt-Waterborne epoxy (CAE)composite cemented materials has been developed, and the composition, structure, properties of the materials has also been studied. The following results are achieved:This paper puts forward a suggestion of CAE composite binding steel bridge deck pavement materials. Introduce the hydroxyl, ether groups to curing agent molecules, mixing and stirring with epoxy resin to emulsify the waterborne epoxy resin. The cement particles adsorbed emulsified asphalt to form the structure asphalt and chemical bonding with the water-based epoxy resin, play a connecting role of media which wrapped in asphalt and epoxy resin. Control the type, particle size and blending proportion of cement, emulsified asphalt and water-based epoxy resin, to form the asphalt and epoxy interpenetrating network structure which connect with cement when the paste harden. The asphalt is the continuous phase of the structure, make the material with good flexibility, and consistent deformation ability with the steel plate; epoxy resin is the modify phase and forming network structure insert with asphalt; cement as the connection medium improve the material Homogeneity and water stability, overcome the epoxy resin (polar) and asphalt (nonpolar) compatibility sent to the problem of layered segregation, and could mix and pouring construction under normal temperature. Improve the problem of rapid curing speed and short time of operation in epoxy asphalt high temperature construction.The principle of Raw material selection, the design and preparation method of CAE was presented, based on researching the rules of the minerals, the fineness and the kinds of cement, the charge and the size of Emulsified Asphalt and Waterborne Epoxy Resin, and the ratio among cement, Emulsified Asphalt and Waterborne Epoxy Resin on the homogeneity, the water stability, the consolidation time, modulus of resilience and the cohesive strength with steel plate of CAE. CAE mortar hardening mechanism and interface characteristics was systematically researched, by using XRD, IR, SEM, EDXA and hydration heat analysis. CAE mortar hardening process mainly includes cementation of asphalt, solidification of epoxy and hydration of cement. The rate of cement hydration, heat release and the degree of hydration is low for the influencing of asphalt and epoxy. Interface of cement-asphalt, cement-epoxy, and asphalt-epoxy is forming after hardening of CAE mortar. Cement-asphalt, asphalt-epoxy interface depend mainly on the physical adsorption and mechanical engagement effect; the bond between the cement-epoxy interface mainly relay on the strong adsorption of the chemical bonding and epoxy polar groups. Cement particles are isolated from aggregate and packed with epoxy and asphalt, the interface of CAE mortar and aggregate is mainly composed of asphalt and epoxy.CAE concrete belong to the viscoelastic material, which static modulus is approached to SMA asphalt concrete. The shear strength, tensile strength is better than SMA asphalt concrete. The anti-fatigue performance and adhesive property with steel plate are equal to the epoxy asphalt concrete level. According to the results of creep test, the Burgers parameters were calculated. Through analyzing the law of the Burgers parameters, the influencing rule of waterborne epoxy resin and cement on sticky elastic mechanics of CAE was researched. Waterborne epoxy resin and cement are good for reducing the flow deformation, delay deformation and increasing temperature stability, and the role of the cement is more marked. Through researching the influencing rule of different temperature, frequency and material composition on the dynamic modulus of CAE, the prediction model of CAE concrete dynamic modulus was established. Based on the phenomenon mechanics method, the CAE concrete bending fatigue equation was established, and the influencing rule of the materials composition on bending fatigue life was analyzing. Through the hot oxygen aging and light oxygen aging test, the relationship between the material composition and the aging performance was analyzed. Research achievements provide a reference for the design and preparation of the new steel box girder bridge deck pavement materials.CAE concrete usability performances were researched. When A/C=2, A/E=5/3,80℃, the CAE, dynamic stability reaches22600times/mm,-10℃low-temperature bending strain reaches2873με, soaking remnants stability and the ratio of freeze-thaw split intensity ratio are greater than90%, shear strength of steel interface reaches1.1MPa, provided with excellent pavement performance.According to the linear-elastic theory and elastic multilayer theory (Muti-layer elastic system), the influencing law of mechanical characteristic were analyzed by ANSYS finite element, which include elastic modulus and thickness changes of steel box girder bridge deck pavement:Along with the increase of in laying thickness of CAE concrete, the maximum transverse tensile stress, maximum transverse tensile strain, vertical maximum displacement are decreased, but the maximum longitudinal tensile stress and maximum longitudinal strain do not changed significantly; The shear stress between paving materials and steel deck surfacing are increasing firstly and then decreasing. For the higher safety, the fit laying thickness of CAE is60mm. On this basis, considering the economic, skid resistance and anti-fatigue performance of the pavement, steel box girder bridge deck pavement structural optimization design program has proposed:Water-based epoxy resin adhesive layer+40cm CAE concrete layer+High viscosity bitumen waterproofing bond stress absorbing layer+40cm high viscosity SMA layer. And the process of CAE construction is drawing up.
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