Research On Preparation And Properties Of Epoxy Asphalt Caulking Material For Ballastless Track Of High-speed Railway

In order to adapt to temperature deformation,a large number of joints are set in the long continuous structure of the high-speed railway ballastless track to prevent water and debris from entering the joints.Existing modified asphalt,polyurethane and silicone caulking materials all have deficiencies,while epoxy asphalt has excellent physical and mechanical properties and can be used as caulking materials for high-speed railway ballastless tracks.Based on the analysis of the stress and deformation characteristics of high-speed railway ballastless tracks,the preparation and related performance characterization of epoxy asphalt materials are carried out,and the construction and use performance of the physical project is verified.First,a static analysis model of CRTS III slab ballastless track containing epoxy asphalt caulking materials is established,and the joint deformation analysis under the influence of various factors is carried out.The technical conditions of caulking materials in related fields are used for reference,and the design is suitable for high-speed railways.The performance test program of epoxy asphalt caulking material for ballast track,including the test program of engineering performance and mechanical performance.Second,on the basis of the existing epoxy asphalt system,through the compatibility test of each component and the direct tensile test,the preparation sequence and the optimal material composition ratio of the epoxy asphalt caulking material are determined to prepare the required materials.Epoxy asphalt caulking material and its engineering performance test,the test results show that the prepared epoxy asphalt caulking material can be used as a high-speed railway ballastless track caulking material.Third,the viscoelastic properties,tensile properties,interfacial bonding properties and compression properties of epoxy asphalt caulking materials under different temperatures are tested.The results show that the epoxy asphalt caulking materials have transition states and rubbers within-20℃～60℃.The tensile strength and bond strength both decrease with the increase of temperature,and the elongation at break and bond elongation first increase and then decrease with the temperature;the tensile performance is always better than the interfacial bonding performance,which is proved that the final failure form of the material is from the seam;the compression properties include compression modulus,compression stress relaxation and compression permanent deformation.The compression modulus decreases with increasing temperature,the compression stress relaxation slows down with increasing temperature,and the maximum compression permanent deformation is 15%.Then,the most unfavorable aging state is determined,and the tensile properties of epoxy asphalt caulking materials with different aging treatments are studied.Through the Verhulst model,a nonlinear dynamic model of microscopic matter and aging time is established.Through thermal analysis kinetics,the effect of aging time and temperature on the interface bonding performance of epoxy asphalt caulking materials is established,and the UV aging process of epoxy asphalt caulking materials is predicted from the microscopic and macroscopic perspectives.Epoxy asphalt caulking materials have cracks on the surface after UV aging and are hydrophilic.Finally,combined with the construction characteristics of epoxy asphalt caulking materials,the physical engineering implementation of epoxy asphalt caulking materials is explored,and the construction technology of epoxy asphalt caulking materials for ballastless track is determined.