Numerical simulation of pavement friction coefficient degradation due to pooling contamination at High-Altitude Airports

To prevent aircraft from skidding off the runway due to degraded friction coefficients caused by water accumulation on runways at High-Altitude Airports, this study employs a combined approach of field testing and numerical simulation. Standard wet runway friction coefficients obtained from field tests serve as critical boundary conditions for finite element numerical simulations. Based on the Navier-Stokes equations, this study pioneers the use of the SPH method to develop a numerical model simulating the interaction among water accumulation, the runway surface, and tires at High-Altitude Airports. Using this model, the study systematically analyzes the influence of main landing gear loads (149.6–165.6 KN), taxiing speeds (10–90 km/h), and water depth (3–13 mm) on runway surface friction coefficients, establishing corresponding theoretical degradation formulas. Key findings are as follows: (1) The friction coefficient exhibits a nonlinear decrease with increasing roll speed. At 60 km/h, the degradation rate transitions from rapid to gradual; (2) The friction coefficient increases with load, showing a phase transition around 161.6 KN: gradual increase before this point, followed by significant growth thereafter; (3) The friction coefficient decreases with increasing water depth, with the degradation process divided into three characteristic stages: the fastest degradation occurs in the thin water film stage (10–13 mm), followed by the 3–7 mm stage, while the degradation rate gradually slows in the stage above 7–10 mm. The findings of this study provide theoretical and practical value for ensuring safe operations on High-Altitude Airport runways under conditions of water accumulation contamination.