Effect of corn and soybean oil derived additives on polymer-modified HMA and WMA master curve construction and dynamic modulus performance

Abstract

In previous work, Isosorbide Distillation Bottoms (IDB), and other isosorbide and soybean based materials with similar properties were shown to act as antistrips in a polymer modified warm mix asphalt (WMA) at a 0.75% dosage level both through visual observations and statistical analysis of Hamburg Wheel Tracking Device (HWTD) test results. Because of this evidence, there is an interest in how specimens produced with isosorbide and soybean bio-derived chemical additives would perform in the dynamic modulus test, as this is the main input used in AASHTOWare Pavement ME in the prediction of rutting performance. The main objective of this research is to compare and contrast dynamic modulus performance of two isosorbide, two soybean bio-derived chemical additive mixtures against each other and controls compacted at both hot mix asphalt (HMA) and WMA compaction temperatures. Master curve modeling with a proposed new (PN) model based on the Yang and You model and Booij and Thoone model for phase angle (δ) master curve construction led to the conclusion that proper placement of coefficients makes it possible to maintain precision and accuracy in the determination of E∗ master curves while co-determining δ master curves. From the master curve results, it was observed that some of the corn and soybean bio-derived chemical additives may be affecting the viscous behavior at intermediate and high test temperatures. Results from statistical analysis were inconclusive, and thus it is felt that further work must be done comparing HMA and WMA produced specimens in the HWTD test.