A Model of Pyrolysis Carbon Black and Waste Chicken Feather Using a Response Surface Method in Hot-Mix Asphalt Mixtures

Research on waste tire pyrolysis carbon black (PCB) in bitumen mixtures indicates that it has excellent high-temperature rutting resistance; however, the degradation of low-temperature crack resistance and water stability of PCB-modified asphalt limits its wide application. Therefore, the low-temperature crack resistance and water stability of PCB-modified hot-mix asphalt (HMA) were enhanced by addition of waste chicken feather (WCF). Based on the response surface methodology (RSM), a variance analysis (ANOVA) and P-value test of the model response coefficient were carried out, and the performance prediction models of percentage air voids (VV) in bituminous mixtures, 30-min Marshall stability (MS), and 48-h MS were obtained. The interaction effects of different independent variables on response variables were analyzed. In addition, the optimal solutions of multiresponse variables obtained by the response optimizer were 0.20% PCB content, 0.36% WCF content, shearing time of 5.78 min for WCF, and 6.66% asphalt-aggregate ratio. The corresponding performance index prediction values were 4.00% VV, 12.80 kN 30-min MS, and 12.65 kN 48-h MS. The road performance test results demonstrated that incorporating WCF improved the high-temperature rutting resistance, low-temperature crack resistance, and water stability of PCB-modified hot-mix asphalt. This study provides a precise performance prediction model for adding PCB and WCF to HMA.