A study has been undertaken to investigate some important factors that influence the permeability of dense graded asphalt pavements. The aim of the study is to develop a data analysis procedure for finding empirical permeability relationships. A number of factors that influence asphalt permeability are reviewed in this paper and the results of laboratory tests on three asphalt mixtures are used to determine the variation of permeability with percent air voids. It is shown that asphalt permeability is influenced by both aggregate grading and air voids. The normalised voids method is validated, using the test data, as a method for improving the relationship between permeability and air voids. A modification to this concept is proposed, termed the 'modified weighted air voids method', which includes the effect of aggregate grading on the regression model for the relationship between permeability and air voids. (a) For the covering entry of this conference, please see ITRD abstract no. E217099.
Samenvatting