Estimation and Evaluation of Water Damage Resistance of Warm-Stone Matrix Asphalt Mixture with Compound Polymer Modifiers Using Regression Tree Ensemble Method

Abstract

Warm mix asphalt (WMA) has recently gained popularity as a pavement engineering alternative because it has the potential to significantly reduce energy utilization and the carbon footprint of the pavement industry. However, due to lower mixing and compaction temperatures, concerns have been raised about the material’s durability and the possibility of water damage. The current research evaluates the effect of the simultaneous usage of two additives [styrene–butadiene rubber (SBR), and polyphosphoric acid (PPA)] on the moisture damage resistance of warm-stone matrix asphalt (SMA) mixtures containing anti-tripping agents (ASAs). Different mixture tests were performed to investigate the moisture susceptibility of the samples. A two-way analysis of variance was performed to investigate whether additives have a significant effect or not. The outcomes show that the combination of two polymers improves the indirect tensile strength, fracture energy, and resilient modulus of samples. Also, the combination of Sasobit and Zycotherm and ASAs enhances the performance of samples, and among mixtures containing ASAs, specimens containing ASA (B) have the best moisture strength performance. In addition, a numerical method through a regression tree ensemble (RTE) model was designed to estimate the resilient modulus ratio (RMR), fracture energy ratio (FER), and tensile strength ratio (TSR) values. The outcomes indicated the high accuracy of this model in predicting the mentioned values.