Sustainable Production of WMA with Pine Gum Wax Modification: Physical and Rheological Evaluation

Abstract Warm mix asphalt (WMA) produced with (S®), which is a common organic additives, (S®-WMA) shows an over-rising softening point value and a decrease in stripping resistance. These two shown behavior of S®-WMA are seen some problems that need to be solved. Because they adversely affect the structural performance of the pavement and therefore, this study is established to evaluate the possible solutions to these two problems by one more modification processes. It was investigated in this study whether modifying S®-WMA by using pine gum wax (PGW), which is a product that has not been investigated before, be a solution to the aforementioned problem. In this context, WMA was produced with S® at 1%, 2% and 3% (by bitumen mass) in 1% increments. Since PGW was not previously used as an additive to modify S®-WMA, it was added within a limit as 1% (by mass of bitumen). Physical and rheological standard tests were performed on each sample in order to demonstrate the variation in the properties of the produced S®-WMA with 1% PGW compared to S®-WMA. The results showed that the addition of 1% PGW to S®-WMA caused significant reduction in the softening point and an improvement in stripping resistance compared to S®-WMA. Thus, it shows that the use of PGW can be a potential solution for the two mentioned problems. It can also be emphasized that S®-WMA sample can be an efficient, economical and environmentally friendly solution by modifying it with PGW without compromising its properties. However, more in-depth research is required due to the use of a limited PGW contribution rate.