DefinePK

Abstract

Asphalt pavement rutting is one of the most commonly observed pavement distresses and is a major safety concern to transportation agencies. Millions of dollars are spent annually to repair rutted asphalt pavements. Researches into improvements of hot-mix asphalt materials mix designs, methods of pavement evaluation and design can provide extended pavement life and significant cost savings in pavement maintenance and rehabilitation. The three objectives of this study are to investigate the rutting behaviour of asphalt mixes with different air void contents, to link these behaviours to an accelerated testing tool using wheel track tester and to develop a finite element model based on creep model parameters. The creep model parameters C1, C2 and C3 were obtained from the dynamic creep test results using multiple regression analysis. The dynamic creep test was conducted at temperature of 40°C using two selected stress levels of 100 and 200 kPa. Five superpave mixes with five levels of air void contents ranged from 2.5-10.5% were used to investigate the rutting behaviour of asphalt mixes. The variation between the value of measured rut depth and the predicted one bye finite element simulation is found to be 4-7%. This illustrates that the developed finite element model can be used in the finite element analysis for giving a good prediction of rutting depth of a bituminous mixture. Three dimensions axisymmetric slice analyses have been used in this study. This study indicated that air void contents have significant influence on the behaviour of rutting under repeated wheel loadings. Finally it can be concluded that creep model based on finite element method can be used as an effective tool to analyze rutting of asphalt pavements.