Effect of geogrid reinforcement on critical responses of bituminous pavements

Abstract

A series of finite element (FE) simulations are carried out to evaluate the benefits of integrating a high modulus geogrid as reinforcement into the pavement layers. This paper presents a two dimensional axisymmetric finite element model that analyzes the behavior of unreinforced and geogrid reinforced bituminous pavement subjected to static and dynamic loading conditions. The critical pavement responses such as fatigue (horizontal) strain, rutting (vertical) strain and vertical surface deflection are calculated for unreinforced and geogrid reinforced flexible pavement using a pavement response model developed through a commercially available finite element program PLAXIS. Parametric studies are performed by varying the location of geogrid reinforcement i.e. base n bituminous concrete interface and the base sub-grade interface. The structural benefits of geogrid reinforcement over fatigue and rutting strain criteria have been quantified. The results obtained are qualitatively compared with the results of published literature and fairly good agreement is found in fatigue and rutting strains in the reinforced pavement. It has been found that placing geogrid reinforcement at the base-bituminous concrete interface leads to the highest reduction in fatigue (horizontal) strain. The highest decrease of vertical strain occurs when the reinforcement is placed at the interface of base and sub grade layers.