Study On Application Of Materials For Steel Deck Pavement Of High-temperature Epoxy Asphalt

The bridge is an aerial route.With the development of science and technology and financial investment,our country has gained the power to construct long-span steel bridges.Nowadays,the overcapacity in the steel industry has also provided new development opportunities for steel bridge undertaking.Nonetheless,due to heavy traffic and harsh climate conditions in our country,there are widespread problems such as bonding layer damage,cracking,delamination or spalling,rutting and other problems in the steel deck pavement,resulting in economic losses and social influence The requirements for the material properties of(steel)bridge deck pavement,as one of the key technologies for bridges,has been increasingly demanding.The paper carries out a study on the curing characteristics and pavement performance of high-temperature epoxy asphalt binder and epoxy resin adhesive layer under independent research and development,thus proposes a high-temperature epoxy asphalt pavement structure which is applicable to steel bridge deck pavement.It was intended to fill the gap for domestic high-temperature epoxy asphalt pavement technology.Firstly,the micro-cured morphology of the high-temperature epoxy asphalt binder was observed by optical microscope.The curing behavior of high temperature epoxy asphalt binder was analyzed from the thermodynamic point of view by differential scanning calorimeter(DSC),and the curing characteristics and curing degree of early period,middle period and late period were summarized.The kinetic parameters of epoxy resin and epoxy asphalt,namely activation energy E and pre-factor A,were calculated by the kinetic equation Kissinger and FWO.The Crane Equation was introduced to infer the curing reaction series of high-temperature epoxy resin and epoxy asphalt.The tensile test was perfonned to acquire the tensile strength and elongation at break of epoxy resin binder and epoxy asphalt binder cured at 150℃with different retention time.From the viscosity-time curve,the changes of viscosity over time at high temperature of high-temperature epoxy asphalt can be observed.Secondly,the optimal asphalt-aggregate ratios for the common grades of high-temperature epoxy asphalt EA-13 and EA-10 were determined and the performance characteristics of the mixture were selected with the EA-10 grading.According to the Marshall Stability Test,it can study on the growth law of strength over time of the high-temperature epoxy asphalt mixture.The rapid opening of transportation in summer was simulated by Marshall Secondary Compaction,it revealed the changes of stability of the mixture.The high and low temperature performance and water stability of high temperature epoxy asphalt mixture were evaluated with set of tests including high temperature rutting,low temperature bending,Immersion Marshall and freeze-thaw split.Among them,the low temperature bending test of EA+SMA was specially designed for the low temperature performance of mixture.The simple performance tester(SPT)was integrated into the analysis,concluding that the dynamic modulus of high-temperature epoxy asphalt mixture at different temperatures and frequencies.With the aid of four-point bending fatigue testing machine of Cooper from U.K.,the fatigue life of high temperature epoxy asphalt mixture at 800με,1000με and 1200με were obtained.Thirdly,the optimal proportion of A and B components of the high temperature epoxy resin adhesive layer was determined by fully considering the tensile strength,elongation at break and thermosetting index.The solidification characteristics of "dry at normal temperature,and meltable at high temperature" of self-made adhesive layer within the validity period were explored.The paper analyzes and verifies the optimum pick-up time of mixture for smearing amount of homemade epoxy resin adhesive layer under 60℃ curing environment were 0.5kg/m2 and 0.7kg/m2.On this basis,the optimal dosage of the waterproof adhesive layer and the adhesive layer were determined by the interlayer pull-out test and tensile-shear test in between the bonding layer and the interlayer pull-out test between steel plate and mixture layer.Through the tensile test,pull-out test,tensile-shear test and low temperature flexibility test,the homemade epoxy resin adhesive layer was compared with three epoxy adhesive layer materials from Japan,the United States and China.Taking mix shear strength between the mixture layers as the core index,it is obtained by oblique shear test between mixture layers that the shear strength of double-layer homogenous structure of EA and double-layer heterogeneous structure of EA+SMA at room temperature and high temperature of 60℃.Ultimately,based on the above research results and relying on the implementation of the project,the paper summarizes construction technology and construction quality control indexes of the high-temperature epoxy asphalt bridge deck pavement,proposing the epoxy asphalt bridge deck pavement structure that is applicable to(steel)bridge deck pavement,namely epoxy resin waterproof adhesive layer+epoxy asphalt concrete+epoxy resin adhesive layer+(high viscosity)SMA asphalt concrete.