Abstract:Uniaxial penetration simulation test method of asphalt mixture was constructed on the basis of two-dimensional particle flow code software PFC2D. The influence of the specimen size, loading rate, calculation step value and other conditions on the results of uniaxial penetration simulation test method was researched, the numerical test standard conditions was determined, the reliability of the uniaxial penetration numerical experiment method was evaluated, and the micro-mechanism of the uniaxial penetration test was analyzed. The results show that numerical can obtain the stable result when the size of specimen is Φ101.6mm×h63.5mm, the loading rate is 1 mm?min-1 and the calculation step is 1×10-3 s.step-1. The simulation curves of penetration strength are basically consistent with the measured curves, uniaxial penetration numerical test error is within 4%. With the increase of loads, the strain increases, micro contact force is more and more intensive and the force is growing, and gradually extended to the specimen bottom; with the increase of the penetration value, the contact force of both sides of specimen gradually intensive, but no significant concentration phenomenon; longitudinal changes is more significant than lateral changes in the contact force network.