In China, the most popular type of pavement is an asphalt concrete pavement with semi-rigid, cement stabilized base. However, most research utilizing the Falling Weight Deflectometer (FWD) has asphalt concrete on a granular base, therefore, there is no standard method to evaluate FWD data from an asphalt concrete pavement with semi-rigid base. This paper analyzed thedeflection basin parameter used to evaluate the strength of a pavement structure with a semi-rigid base. Based on calculations of a typical asphaltconcrete pavement structure with a semi-rigid base, using BISAR, a sensitivity analysis was applied. The result indicated layer modulus significantly impacts the deflection basin parameter. According to these results andstress diffusion angle theory, multiple deflection basin parameters are proposed to represent each layer modulus. Through a correlation analysis, all parameters were validated from data of JingHu Freeway in China. As a result, a group of parameters was determined as optimal in representing layer modulus. Furthermore, regression formulas were established for each parameter and its corresponding layer modulus. With these parameters and formulas, modulus calculation and evaluation of each pavement layer will be more straightforward in an asphalt concrete pavement with a semi-rigid base.
Abstract