Interlaminar Shear Stress and Structure of Continuously Reinforced Concrete Composite Asphalt Pavements

Abstract

This study calculated and analyzed the critical load position and influencing factors of interlaminar shear stress, with focus on the characteristics of and existing studies on continuously reinforced concrete and asphalt concrete (CRC + AC) composite pavement structure. The calculation and analysis were conducted using heat transfer theory, mechanics theory, and finite element method. Interlaminar structure and materials, as well as technology for CRC layer surface treatment, were investigated through indoor experiments and engineering application examples on the basis of interlaminar shear stress. Results show the following: (1) Longitudinal and lateral slips occur in CRC + AC structure because of weak interlaminar shear strength. (2) Interlaminar maximum shear stress decreases as the thickness and modulus of the AC layer increase, with the decrease trend being more obvious with increasing thickness of the AC layer. This trend is also observed along with the minimal effect of the thickness of the CRC layer on interlaminar maximum shear stress. As indicated by the analysis and calculations, combined with the measurements and construction experience of test road, the recommended thickness for AC layer is no less than 6 cm. It is recommended the spraying-type structure should use to treat the interlayer of CRC + AC structure, SBS modified asphalt use as spraying asphalt, and the baring technique use to treat the surface of CRC layer. These results can serve as important reference for the rational design of rigid-flexible composite asphalt pavements.