Thermal Stresses of Asphalt Overlay on Cement Concrete Pavement (Ⅰ):Mechanistic Models

Abstract:

The paper presents a comparative study of the applicability of solid model, plane model and bilayer beams on elastic foundation model which are employed to analyze the thermal stresses of asphalt overlay paved on cement concrete pavement slabs.Study results show that it is feasible to represent the structural deformation of asphalt overlay by means of superposition of deformations occurring in two sets of beams perpendicular to each other. Due to the discontinuity at the joints of cement concrete pavement slabs, the thermal stresses of asphalt overlay near the joints concentrate remankably,and are more difficult to converge than sectional inner forces (axial force, sectional moment).It is appropriate to describe the stress state of asphalt overlay with the sectional inner forces.By adjusting the coefficients of horizontal shear and uniaxial tensioncompression effects, the sectional inner forces of asphalt overlay obtained with bilayer beams model agrees well with that based upon plane model.

Key words:road engineering; asphalt overlay; thermal stress; mechanistic models; finite element; bilayer beams model