Stochastic vibration analysis of aircraft-rigid pavement system under random aircraft parameters

The dynamic response analysis of aircraft and rigid pavement is critical for runway design and roughness evaluation. Existing methods typically assume fixed aircraft parameters, but actual variations in aircraft weight, landing gear, and tire characteristics can significantly impact the dynamic interactions between the aircraft and the runway, thereby influencing performance evaluation. This study develops a coupled aircraft-rigid pavement stochastic vibration model incorporating measured runway roughness data from three runways. The model is then employed to analyse the impact of aircraft parameter variations on pilot station acceleration (PSA) and the longitudinal tensile strain at the bottom of the rigid pavement surface layer, induced by vertical wheel loads. The results demonstrate that aircraft weight has the most significant effect on system responses, with normalized coefficients of variation of 60% and 101% for PSA and pavement strain, respectively. On runways with poor surface conditions, accounting for parameter randomness can lead to a shift in PSA from acceptable to unacceptable, and the difference in allowable load cycles for pavement structures can reach 235%. This significant influence underscores the necessity of considering aircraft parameter variability to improve safety assessment accuracy.