0000000000319684
AUTHOR
Lily D. Poulikakos
Can crumb rubber modifier effectively replace the use of polymer- modified bitumen in asphalt mixture?
Laboratory scale mechanical performances on six plant produced mixtures; three semi-dense surface courses and three dense binder courses modified with engineered crumb rubber (ECR) using the dry process are presented. The two types of mixtures produced and investigated fulfilled for the most part, the requirements of the Swiss and/or US standards regarding volumetric properties, water sensitivity and rutting. In advanced testing where no requirements exist, the dense ECR mixtures performed similar to the reference polymer modified mixtures and slightly worse for semi-dense mixtures in high temperature tests, where the binder becomes viscous in the rubber-binder composite and its ability to …
Life Cycle Assessment of Asphalt Mixtures with WMR
This study aimed at providing pavement specialists with international average values of greenhouse gas emissions (GHG) and energy consumption related to the manufacturing of asphalt mixtures (cradle-to-gate), with and without waste and secondary materials for roads (WMRs). In order to achieve this goal, TG leaders first referred to current standards to define a methodology for obtaining benchmark values according to ISO 21678:2020. Then, a data collection tool was designed and provided to a group of international partners to build a life cycle inventory for asphalt mixtures including data from materials up to plant manufacturing (A1–A3). Partners were asked to provide information for any ty…
Rheological Behaviors of Waste Polyethylene Modified Asphalt Binder: Statistical Analysis of Interlaboratory Testing Results
This article investigated the effect of waste polyethylene (PE) on the modified asphalt binders' rheological behavior from a statistical point of view. The interlaboratory testing results from the RILEM Technical Committee 279 Valorization of Waste and Secondary Materials for Roads Task Group 1 were used for this purpose. First, an unaged 70/100 penetration graded neat binder was selected as the reference material. Next, a single 5 % content of waste PE additives (PE-pellets and PE-shreds) was mixed with a 95 % neat binder to prepare two PE modified binders. Then, dynamic shear rheometer-based temperature-frequency sweep tests were performed over a wide range of temperatures and frequencies…
RILEM TC 279 WMR round robin study on waste polyethylene modified bituminous binders: advantages and challenges
inter-laboratory experiments were designed to evaluate the impact of plas- tic waste blended directly in bitumen and to assess the properties, using conventional and advanced bituminous binder testing. The blends tar- geted 5% of plastic waste in 95% bitumen, using two types of polyethy- lene (PE) primary (pellets) and secondary (shreds) waste. The experiments showed that the addition of PE waste to bitumen does not alter the chem- istry of the bitumen, the blending is physical. The DSR results indicate a strong dependency on the testing temperature as at low temperatures the composite material bitumen and PE behave both elastically whereas, at higher temperatures, the bitumen becomes visco…