Research On Deformation Property Of Asphalt Mixture Based On Digital Image Correlation

Asphalt mixture deforms under the load, accumulation of deformation cause the rutting problem, the crack appears when the deformation is beyond the confine of deformation resistance?rut and crack is the main failure of asphalt pavement and effect the pavement performance, therefore the research of deformation property is important for the pavement performance. Asphalt mixture is the composite multiphase material, because of the difference between materials in the asphalt mixture, the deformation property is complicated. Traditional deformation measure method can hardly get local deformation property of the asphalt mixture, additionally, heterogeneity of asphalt mixture cause the randomness of failure position?therefore it is diffcult to set the deformation sensor accurately. Digital image correlation provide a new method to measure the local deformation, it is convenient to measure the deformation of failure position based on the full field strain. Based on the advantage of measuring deformation of asphalt mixture by digital image correlation, this research focus on the following aspects:(1) Reseach of experiment method and software parameter choiceResearch the basic theory, test equipment, test process and software post process of digital image correlation. Research the parameter for digital image correlation test system, analysis the effect of the parameter on the test accuracy.(2) Research of the strain field of asphalt mixture and the establishment of deformation property evaluation criteriaGet the strain field of asphalt mixture based on the result of different test method with different kinds of asphalt mixture. According to the result from digital image correlation software, propose the deformation property evaluation criteria.(3) The effect of heterogeneity on the deformation property of asphalt mixtureCompare the heterogeneity of asphalt mixture and strain field, propose the heterogeneity evaluation criteria of asphalt mixture, establish the relationship between heterogeneity of asphalt mixture and strain field based on the heterogeneity evaluation criteria.(4) The influence factors of deformation property of asphalt mixtureAnalysis the influence factors of deformation property of asphalt mixture, get the difference in the macroscopic deformation test results and digital image correlation analytical results according to changing the influence factors, get the key factors for different test results.(5) Research of fracture property of asphalt mixtureAccording to the fracture property test, analysis the discrepancy in the macroscopic mechanics and deformation property between different materials, propose the fracture evaluation criteria using digital image correlation method, analysis the different in the digital image correlation fracture evaluation criteria between different materials.