Flood impact on structural response of asphalt pavement: A finite element modeling approach

Abstract

The frequency and intensity of floods have increased due to climate change. These natural events negatively affect asphalt pavements, submerging their layers and reducing structural resistance. This work introduces a computational finite element model suitable for investigating the impact of floods on asphalt pavement response. Unlike previous works, which consider a multi-layer analysis, in this research, the resilient modulus varies locally as a function of moisture, which could be variable in the transverse direction of the cross-section. The moisture distribution in the pavement structure is found by solving the Richards’ equation through non-linear finite element analysis. This moisture distribution is coupled to the three-dimensional elasticity problem to find the structural response to traffic loads. The structural problem was solved using the semi-analytical finite element method. Results show that the reduction of the resilient modulus in the unbound and subgrade layers is heterogeneous, with the areas near the edges of the pavement being the most affected. It was also found that the increase in elastic surface deflection depends on both the load position and time, which suggests the damage caused by vehicles could be different for each wheel path, depending on the time in which the vehicles circulate. This research presents a valuable tool for evaluating the impact of flooding on asphalt pavement structures.