| Nearly90%asphalt roads use semi-rigid base pavement in our country. Thesemi-rigid pavement is easy to produce crack in the effect of temperature and loading.Under the effect of the long-term vehicle load and climate temperature changes,grassroots crack expands upward to the asphalt surface. Even penetrate the surface,result serious reflectivity crack problems. It is very important to improve theanti-crack research of the asphalt pavement emission cracks and meliorate the designand calculation of the existing pavement, carry out the formation and extensionbehavior of asphalt road reflectivity crack, understand the mechanism of the roadearly destruction.In this paper, based on the related information domestic and overseas and studyof existing research results, using the nonlinear contact-impact program ABAQUS,considering the viscoelastic characteristics of mixture asphalt, build up the finiteelement model of the road system with reflective cracking. Analyses the latticestructure layer of asphalt pavement temperature field under the change of lowatmospheric temperature in a day. Consider the influences of different vehicle speedsand base course modulus upon the displacement field and stress field of the crackingroad surface’s structural system. The calculation results indicate that the climatetemperature changes only impact the road architecture near the surface. And thetemperature field changes lagging behind the temperature changes in road system. Thestress intensity factor curve of crack tip moved with vehicle speed increasing, and thecrest value almost not fluctuate. The stress intensity factor increased with the increaseof base course modulus；Under the effect of deflected load,the crack tip stressintensity factor are comprised of KⅠ、KⅡ.When the base course modulus is relativelysmall, Crack tip stress intensity factor is represented KⅡ, with the increase of theelastic modulus KⅠincreased,and KⅡalmost remains invariable. |
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