Structural Response of a Cement Concrete Pavement with a Buffer Layer to Temperature and Moving-Load Effects

The main issues associated with cement concrete pavements are cracks and broken plates that affect driving comfort and road service life. To ensure sustainable use of the cement concrete, a buffer layer (AC-10) can be introduced between the base and the cement concrete panel. In this study, the interlayer shear test was performed, and the interlayer bonding coefficient under different temperature conditions was determined. The creep test of the buffer layer was also conducted, and the four parameters (E1, E2, eta 1, and eta 2) of the Burgers model of the buffer layer were analyzed using regression. According to the parameters obtained from the test, the finite-element model was established, and the moving load was applied to analyze the structural model response under high-, medium-, and low-temperature conditions. The results show that the (1) temperature stress is mainly concentrated in the buffer layer and regions above the structural layer. At low temperatures, the maximum stress at the top of the surface layer is 2.16 MPa, and the vertical strain decreases as a function of depth. (2) Under the combined action of temperature and moving load, the variation ranges of tensile and compressive stresses at the top of the surface layer are the largest; the variation range of the buffer layer and the subsequent structure is small; the maximum warpage deformation of the surface layer is 0.453 mm under high-temperature conditions; and the maximum compression deformation is 0.219 mm under low-temperature conditions. (3) The comprehensive coefficient kc of the fatigue equation was modified, and the comprehensive coefficient kc of the fatigue equation under different vehicle speeds was proposed. This study provides a reference for the sustainable development of cement concrete pavements with buffer layers.