The conversion relationship between power spectral density (PSD) and international roughness index (IRI) was studied based on the filtering white noise method with variable sampling frequency using a quarter vehicle model. Six-degree-of-freedom dynamic equations of the whole aircraft taxiing were obtained considering the lift, upstream and downward bump, roll and pitch motion of the airframe. And then the dynamic load factors of the aircraft wheels under different pavement roughness and various airspeeds were solved by SIMULINK toolbox. The results shown that the mean dynamic load is independent of the pavement roughness, whose values are approximately equal to the load when the aircraft glided on the smooth pavement. The worse the pavement roughness, the greater the maximum dynamic load factor. There are approximately linear relationships between IRI and the maximum dynamic load. When the aircraft glides at low airspeed, the dynamic load increases as the increasing of airspeed. Then the maximum dynamic load factor decreases with the increase of running velocity. Moreover, the formulas for calculating the wheel dynamic load factor under the coupling action of pavement roughness and airspeed were proposed, which could be used to calculated the distribution of the dynamic load in longitudinal direction of the runway and determine the dynamic load values in airport pavement design.

In order to determine the key content of preventive maintenance of the cement concrete pavement in military airports in the seasonal frozen area, the relationship among pavement diseases is analyzed in this paper, and the degree of impact of each disease on pavement damage is quantified. Based on the survey data of 36 sample airports in 12 provinces, such as Hebei, Shandong, and Liaoning, a questionnaire covering many disease variables affecting pavement damage was designed. The exploratory factor analysis method and structural equation model (SEM) were used to analyze the interaction among joint disease, surface disease, vertical disease, repair disease, and fracture disease. And the influence degree of each disease on pavement damage was quantified as well. The research results show that the questionnaire has good reliability and validity and is suitable for confirmatory factor analysis. The SEM fits well with the observed data and meets the adaptation standard. Joint disease, surface disease, and vertical disease all have significant positive direct impact on pavement damage. Moreover, joint disease and surface disease can also indirectly affect pavement damage. The effects of surface disease (0.327), vertical disease (0.283), and joint disease (0.219) on pavement damage decrease in turn. Surface diseases have the greatest impact on pavement damage, which are the critical diseases to accelerate the pavement damage. By strengthening the prevention and control of surface diseases and delaying the conversion process of other diseases to surface diseases, the service life of the pavement can be greatly improved, and the maintenance cost can be reduced.

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