Visco-elastic-plastic Model Research On Hot Asphalt Mix During The Field Compaction Stage

At present, the compaction technologies at the construction of asphalt pavement has been aroused widespread concern. All aspects of asphalt pavement compaction research system in China is not deep and enough, still in the initial stage which rely on the experience, especially, the heat flow research for the mechanical properties of asphalt mixture in compact construction is still incomplete. In this paper, based on the research subject, specific to hot asphalt mix during the field compaction stage, the study is carried on for visco-elastic-plastic model.First of all, on the basis of the asphalt mixture compaction mechanism , a brief to the current asphalt mixture states rheological mechanics research is given, summarized and classified them to compare their respective advantages and disadvantages, then reflect a rheological properties of thermal visco-elastic-plastic model for a compaction pavement materials, and the Bodner-Partom model based on high temperature, large deformation is evaluated.Secondly, taken into account the temperature and lateral limits for the material properties of asphalt mixture, the conventional uniaxial compression test is improved. Such as the of test mold and test methods. Through MTS uniaxial compression creep test on custom-made large-diameter cylindrical specimen, the problem of the temperature changes and lateral limits are solved, and the strain curves from the test of asphalt mixture are given.Thirdly, through an analysis of test data, observed the six kinds HMA of different density under the early pressure under different loading, the stress and strain changes in the law is given, and a comparative analysis is under the table; Through the custom modules of Bodnet-Partom model in Origin, using this data analysis software to do non-linear response curve fitting, all parameters contained in Bodnet-Partom model are calculated, and the change law of the parameters under the different density is analyzed.Finally, the 3D numerical simulations of ANSYS software for the laboratory test are carried out, given full consideration to the rheological properties of materials, large deformation and creep phenomena, and the change law by the non-linear displacement, stress curves are as analyzed. Then ANSYS model, the theoretical curve of calculated and experimental curves, Bodner-Partom model for a comparative analysis of curve fitting.