关键词: 道路工程, 高性能RAP料, 柔性基层, 重载, 力学响应, 分布特性

Abstract: Based on the reform and expansion project of 308 State Road from Nangong to Shixing，the mechanical response of pavement structure of high-performance RAP material flexible base under the condition of overloading was analyzed.The surface deflection，horizontal tension strain，the top compression strain of the remaining base layer of the old road and shearing stress of pavement structure of high-performance RAP material flexible base under five different load levels were comparatively analyzed by ABAQUS software，the distribution and the variation rule of them changing with load level were analyzed as well.The result shows that：the surface deflection distributes as a “W” in the X direction，and reaches its maximum value at the center of single wheel.With the gradual increase of depth，the surface layer is transformed into tensile strain from the pressure strain；and along with the increase of the axial load，the compression strain moves downward along the vertical direction；the top compression strain of the remaining base layer of the old road as a “U” in the X direction，and reaches its maximum value at the center of the wheel track；the shear stress shows a sine distribution in the transverse direction，reaches the maximum value at the edge of the wheel track and occurs in the range of 45cm depth below the surface of the surface layer in Y direction；under the same axle load，the mechanical response of pavement structure of high-performance RAP material flexible base is less than that of the graded crushed stone pavement structure.With the increase of axial load，both the mechanical responses of pavement structures increase，and the mechanical response of pavement structure of high-performance RAP material flexible base shows a slow increase.

Key words: highway engineering, high-performance RAP material, flexible base, overloading, mechanical response, distribution features