LAUSR

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.