Study on the Rational Thickness of Surface Course on Semi-Rigid Base Asphalt Pavement

Proceeding from the mechanical characteristics of semi-rigid base asphalt pavement, using pavement calculating program, flexural tensile stresses at the bottom of subbase in the condition of different thickness of surface course, base and subbase were calculated respectively in this paper. The influence of different material modulus on the flexural tensile stress at the bottom of every layer was studied. Then, the state of shear stress distribution in the asphalt surface layer under different surface course thickness was analyzed. The purpose was to investigate the effect of surface course thickness to the stress characteristics of semi-rigid base asphalt pavement. The results indicated that the influence of surface course thickness on the bottom flexural tensile stresses of pavement structural layers was not significant. The surface course thickness required by the mechanical property was not bigger. According to these results, for the economic benefit, a rational surface course thickness scope of semi-rigid base asphalt pavement that met the functional requirements was proposed in this paper.