Modeling of dynamic phenomena in road and airport pavements

The interaction between moving wheel load and road/airport pavement had a great impact on researcher in different engineering branches (mechanical, road and transportation etc.), in particular when studying the consequences of deterioration on pavement and vehicle. The main implications are transportation safety and comfort, besides economical, environmental and management issues. The motion of a vehicle on a pavement structure (that is never perfectly flat) produces always dynamic actions, higher than static ones, that depend on the roughness of the road surface, the vehicle characteristics and their speed. Traditionally the dynamic loads, applied on a uneven surface are calculated using a lumped masses rheologic models, that are represented and solved mathematically with a system of differential equations. The loads resulting from the solution of this system are applied “statically” to the pavement model, to evaluate the pseudo-dynamic action induced in the pavement layers and subgrade. The dynamic actions can be studied also by means of a innovative approach using a 3D FEM simulations, performed by dynamic nonlinear codes, like LS-DYNA. These models are able to reproduce the most frequent operating conditions of road and airport pavement. In this way it is possible to examine various phenomena, such as the presence of a potholes in the road surface, the bridge expansion joints and the faulted construction joints in rigid pavement under heavy dynamic loads. FEM model results can be used to verify the overpass of the limit conditions of the principal components of transport (user, vehicle, infrastructure, environment). Particularly this research can define the admissible limits of road and airport surface evenness for the transport heavy loads.