PPRC11 SPE 4.41.2: Laboratory and Accelerated Pavement Testing (APT) of Gap-Graded Rubberized Mixes (Hot Mix Asphalt and Warm Mix Asphalt) for the Department of Resource Recycling and Recovery (CalRecycle). Subtitle: Warm-Mix Asphalt Study: Evaluation of Rubberized Hot- and Warm-Mix Asphalt with Respect to Emissions.

摘要

In recent years, warm mix asphalt (WMA) technologies have been used to modify asphalt binders, with the aims of decreasing production and construction temperatures, reducing fumes and emissions, retaining the properties of the mix during long haul distances, and improving workability. Reduced production temperatures at the plant and during paving and compaction are believed to reduce emissions from the asphalt. The objective of this research study was to quantify the potential environmental benefits during paving operations with respect to the reduction of volatile and semi-volatile organic compounds and polycyclic aromatic hydrocarbons to confirm or refute this hypothesis. Asphalt plant stack emissions were not assessed as part of this study. A portable “flux” chamber was designed and fabricated to capture and directly measure emissions during paving operations. An analytical method was developed to identify and quantify alkane emissions using gas chromatography mass spectrometry (GC-MS). A separate method was developed for identification and characterization of trace level polycyclic aromatic hydrocarbon compounds in the asphalt fumes. The results demonstrated that the warm-mix asphalt technology type, plant mixing temperature, and level of compaction significantly influence emissions characteristics throughout paving operations. Depending on these variables, most warm-mix technologies appear to have potential for reducing emissions during transport and paving operations