Hybrid life cycle assessment for asphalt mixtures with high RAP content

Considerations on the Benefits of Using Recyclable Materials for Road Construction

“…Case studies by Huang et al reported that the use of 25% RAP and 10% of fly ash contributed to a 4% reduction in total energy consumed for the production and layout of the mix as well as CO2 emissions [9]. Another study by Aurangzeb et al found that the use of 30%, 40%, and 50% of RAPs decreased energy and CO2 consumption by 7.3%, 9.8% and 12.2%, respectively, compared to the situation where the PAP was not used [10]. Finally, a recent study by the US Environmental Protection Agency (US EPA) reported that using 25% of RAPs reduced greenhouse gas emissions by up to 16%, highlighting the importance of use of recycled materials.…”

Life cycle assessment of pavements: reviewing research challenges and opportunities

“…transportation after raw materials production) of the life cycle was assigned to that phase ( presented as a separate phase (Zhang et al 2008), where in others, M&R is defined as a standalone phase (Butt et al 2012, Aurangzeb et al 2014. EOF and use phase were frequently not considered, because of the cut-off approach b (in the case of EOF) (Meinshausen 2013, Celauro et al 2015.…”

Environmental and economic analyses of recycled asphalt concrete mixtures based on material production and potential performance

“…Aurangzeb et al (2014) examined the environmental footprint of asphalt mixtures prepared with high RAP content. The authors observed reductions in energy and GHGs of up to 12.2% with mixtures prepared with 50% recycled RAP material.…”

“…At some point, the extra fuel will offset any environmental or energy savings from the material production phase. The level of pavement performance at which this occurs can be represented by a "breakeven" service life, as first used by Aurangzeb et al (2014). It should be noted that the breakeven service life can also be greater than 15 years if the performance of the evaluated overlay is better than the baseline overlay performance as predicted in the IRI progression model.…”