Abstract
For the purpose of establishing a repair design method of asphalt pavements for the Japanese expressways, the nationwide research of pavement structure using FWD was conducted there. As a result, it was considered that strength of asphalt layers' structure contribute reduction of deflection. It was also found that there is a slight relation between deflection difference (D0-D90) and summation of layer's thickness to multiply resilient modulus of the asphalt cores sampled from the loading point in the field..
