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Crumb rubber (CR) and ethylene vinyl acetate copolymer (EVA) were adopted as asphalt modifiers. Routine tests, softening point, penetration, and ductility were used to evaluate the basic properties of crumb rubber and ethylene vinyl acetate copolymers (CR/EVA) modified asphalt. The segregation experiment measured the storage stability. Modern test methods such as fluorescence microscopic photography technology was used to study stability of polymer modified asphalt. Infrared spectrum experiment was used to analyze the composition differences of the upper part and lower part of CR/EVA modified asphalt. Matlab software was employed to fit out the formulae of ductility, penetration, and softening point difference of modified asphalt and shearing temperature, shearing time and shearing rate separately. Compared with base asphalt, the properties of CR/EVA modified asphalt have been greatly improved. The formulae which were fitted out by Matlab software showed that the shearing time was the foremost factor affecting the properties of CR/EVA modified asphalt, followed by shearing temperature, and the last was shearing rate. The conclusions which were fitted by orthogonal experiment were basically consistent with the results of formulae which were fitted out by Matlab software.

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In this paper, thermoelastic problem of onedimensional copper rod under thermal shock is simulated using molecular dynamics method by adopting embedded atom method potential. The rod is on axis x, the left outermost surface of which is traction free and the right outermost surface is fixed. Free boundary condition is imposed on the outermost surfaces in direction y and z. The left and right ends of the rod are subjected to hot and cold baths, respectively. Temperature, displacement and stress distributions are obtained along the rod at different moments, which are shown to be limited in the mobile region, indicating that the heat propagation speed is limited rather than infinite. This is consistent with the prediction given by generalized thermoelastic theory. From simulation results we find that the speed of heat conduction is the same as the speed of thermal stress wave. In the present paper, the simulations are conducted using the large-scale atomic/molecular massively parallel simulator and completed visualization software.