BEHAVIOR OF AIRPORT FLEXIBLE PAVEMENT OVER SWELLING SOIL REINFORCED BY NEW ASPHALT LAYERS
Longitudinal fractures are a common occurrence in runway pavements built on expansive soil subgrades. Such soil behavior leads to a reduction in the carrying capacity and lifespan of runways, as variations in water content accelerate cracking and deformations in the various pavement construction layers. To examine the behavior of reinforced runway flexible pavement over expanding subgrade soil, this study uses experimental and numerical analyses. Non-destructive deflection test is used to assess static behavior, measuring deformations and stresses in various runway profiles both before and after reinforcing with new asphalt layers created using the ACN-PCN process. Using the software program PLAXIS 3D, a three-dimensional (3D) finite element model (FEM) was designed to anticipate pavement distortions resulting from sudden, high-pressure movements caused by the expansion of soil. The materials were simulated using a soft-soil model (SSM) for the expanding subgrade and nonlinear behavior for the pavement layers. The experimental results and computer analyses were compared, and it was discovered that the measured and calculated deflection curves generally match very well.
Keywords: Swelling Subgrade; Flexible Pavement; Runway; Strengthening; (3d) Model.