Evaluation of rutting potential of hot mix asphalt in variable conditions

Abstract

Flexible pavements are designed to withstand structural and functional failures. Rutting or permanent deformation is a structural defect associated with functional implications that most common found in flexible pavement. It is mainly caused by wheel loads and accelerated by environmental factors. Although rutting is contributed to by all five layers in flexible pavement, the behaviour of the wearing course is the least understood and contributes significant effect on the overall performance of pavement, therefore, this study was conducted to identify the rutting behaviour of the wearing course subjected to repetitive vehicle loading and exposed to different environments. This study was performed on a 22.6 m stretch of pavement consisting of two mixes, namely ACW14 and ACW20, and subjected to repetitive loading and exposure to various environmental effects such as wet stretches, heat conditions and spillage of petrol, diesel and cooking oil, for each test, a section of rat was measured every 50 cycles of the wheel track, which weighed 280kg. A multivariate regression analysis was carried out to determine the relationship between fut depth and the number of wheel track passes. the results showed that exposure to petrol and diesel on pavement has a very detrimental effect as compared with other conditions.