Abstract: The local support deterioration of asphalt concrete pavement is one of the main factors causing its disease. Considering the different deterioration degree of pavement base and subgrade, the deterioration of support material is achieved by the reduction of the mechanical parameters . The numerical simulation is carried out by FLAC3D software. The results show that with the increase of deterioration degree, the deflection and tensile stress of asphalt concrete pavement increase gradually. Besides, the maximum deflection of asphalt concrete pavement decreases in a power function with the increase of deterioration coefficient. When the deterioration area ratio is greater than 1, the pavement deflection increases linearly with the deterioration area ratio. With the development of deterioration depth, pavement deflection value can be divided into rapid increase stage and slow change stage obviously. When the critical depth is exceeded, the influence of support deterioration on pavement deflection is not obvious. The research results have reference significance for improving the operation safety of asphalt pavement under the condition of disease.

Key words: asphalt concrete pavement, disease, strength deterioration, numerical simulation