3D finite element modeling the response of multi-layered flexible pavement under axle loads

Advanced finite element methods are utilized to simulate the behavior of multi-layered flexible pavements under various axle load configurations, leading to improved predictions of pavement performance. The comprehensive three- dimensional finite element method (3D-FEM) offers a detailed understanding of pavement mechanics, considering static loads and the intricate interactions between pavement layers and vehicles. The finite element (FE) model was meticulously crafted using the ABAQUS FE program, incorporating a constitutive model for granular material and asphalt concrete (AC) surfaces through a specialized subroutine. The response of each pavement layer to stress is influenced by its unique material properties, with the multilayer elastic analysis assuming stationary loads. To model the surface layer of asphalt concrete (AC), a viscoelastic approach was adopted, recognizing that all layers, including the subgrade, may exhibit nonlinear behavior. The primary aim of this research is to predict rut depth, stress levels, and strain distribution resulting from different axle loads configurations such as single axle-dual wheel, tandem axle-dual wheel, and tridem axle-dual wheel. Through a series of analyses, it was observed that rut depth, stress, and strain increased proportionally with higher axle loads. Specifically, compared to single axles, tandem axles showed an approximate 32% increase in rut depth, while tridem axles exhibited an 85% increase. These findings offer valuable insights into the response mechanisms of multi-layered flexible pavements and contribute significantly to the advancement of more precise and reliable analysis techniques for flexible pavement structures.