| The most form of the built highway in our country is semi-rigid base asphaltpavement now．But the semi-rigid base easily gives early to shrinkage cracking withthe change of temperature and humidity. This produces reflection crack in asphaltsurface, further results in other diseases, and works severity early damage. Meanwhile,along with the rapid economic development in our country, the modern highwaytransportation characterized with high traffic density, high load and channelizedtraffic, so the mechanic responses of asphalt pavement changed also. But there arestill some imperfections in the current highway design standard of our country. Forexample, it didn’t take the index of shear stress, the gradient characteristics ofpavement modulus and the non-uniform distribution characteristics of load intoconsideration. In view of this, the inversion structure is a pavement structure formthat can effectively reduce reflection cracking. It can reduce stressing concentration，enhance the anti-fatigue properties of pavement，delay development of cracking．Andif under the premise of the reasonable structure design, the inversion structure canbear the heavy traffic fatigue effect well. So it was necessary to extend the researchon the mechanical properties of inversion structure. This thesis makes use of finiteelement analysis program to research. The primary contents are as follows:(1) Based on linear elasticity theory, the three-dimension model was establishedto study the structure design of inversion structure. At last, it was concluded thatwhen the graded stone transitional layer posses with enough strength and the modulusabove350Mpa, the inversion structure can performed well in our country’s highway.And the reasonable thickness of asphalt pavement in inverted structure is analyzed.(2) The gradient model which accounts for the material parameters’ gradientchange along the depth direction and the homogenous model will be built，calculatedand analyzed, to comparative analyses the differences of pavement mechanicalproperties under the high and low temperature field and by the long-term aging.(3) According to the tire tread pattern is different, a simplified model of contactarea was built, and then the contact pressure distribution form was presented refer tothe relevant measured results. At last the non-uniform load pavement model wasestablished to analyze its influence on responses of asphalt pavements. |
