BEHAVIOUR OF DIFFERENT PAVEMENT TYPES UNDER TRAFFIC LOADS USING FINITE ELEMENT MODELLING

Finite Element Modelling (FEM) has become an increasingly popular method to help researchers find solutions to complex problems of structural mechanics in engineering. Pavement is a complex structure which consists of multiple layers of different materials that influence its behaviour under stress. Rutting behaviour can be predicted by 3D model analysis using the ABAQUS program. The modelling process assumes that the performance of all materials is one of linear elastic behaviour. The main inputs in the modelling process are the material elastic modulus, Poisson's ratio and layer thickness. Models consist of surface, base, subbase and subgrade layers. Subgrade layers are assumed to have infinite depth in all pavement models. This study employed a simulation process of rigid, semi-rigid and flexible pavements using a standard axle load of 80 kN, which represents a single two-wheeled axle. FEM analysis showed that instantaneous vertical displacement along the Z-axis reached 0.105 mm, 0.32 mm and 0.66 mm for rigid, semi-rigid and flexible pavements respectively. Increasing the subgrade elastic modulus from 10 MPa to 200 MPa decreased the vertical displacement by seven, six and a half, and three and a half times for rigid, semirigid and flexible pavement respectively. KENLAYER results refer to the maximum vertical displacements as being 0.1, 0.28 and 0.60 mm for rigid, semi-rigid and flexible pavement respectively. The subgrade elastic modulus is key to improving the resistance to failure of all pavement types. Incremental increase to the subgrade elastic modulus is a potential engineering solution to reducing vertical displacement