Abstract:

Based on the theory of layered elastic system , first , the moduli of asphalt surface course were backcalculated according to the surficial deflection responses of pavement structure. Next , a database of the structural parameters and the corresponding surface deflections was established according to the offsets of geophones set on the falling weight deflectometer to the center of load plate. Then , the critical influencing thickness of asphalt surface course was brought up after analyzing the database. Finally , regressive models were developed according to the corresponding critical influencing thickness. It is shown , from the comparative analyses of theoretical and measured deflection basins , that the proposed method is practical and effective in rapidly evaluating pavement bearing capacity with high accuracy and good reliability.

Key words: bituminous pavement, asphalt surface curvature index, critical influencing thickness, elastic modulus, backcalculation, layered elastic theory, falling weight deflectometer