TY - JOUR
T1 - Lifecycle Analysis of Recycled Asphalt Pavements
T2 - Case Study Scenario Analyses of an Urban Highway Section
AU - Hasan, Aisha
AU - Hasan, Umair
AU - Whyte, Andrew
AU - Al Jassmi, Hamad
N1 - Funding Information:
This research project is supported by an Australian Government Research Training Program (RTP) scholarship.
Publisher Copyright:
© 2022 by the authors.
PY - 2022/6
Y1 - 2022/6
N2 - Roads account for a major part of energy/resource consumption and emission of GHGs, such as CO2, PM, NOx, O3, etc., due to high demand for virgin materials, specifically in developing regions. The applicability of recycled materials, such as recycled asphalt pavement (RAP) and other alternative approaches for, e.g., warm-mix asphalt (WMA), in developed countries is hindered by project-specific constraints and lack of empirical studies in these regions. Lifecycle assessment studies on the usage of these road options from actual projects in the developing countries can aid decision makers choose sustainable material approaches by providing case study examples as guidelines. To that end, this study analyses environmental in/out-flows for a traditional approach and multiple green approaches (RAP and WMA) for a major highway section in Abu Dhabi through a 30-year (2015–2045) lifecycle approach. Roadworks were modelled in SimaPro according to real-world conditions, and the expected burden mitigation in each stage is calculated. Benefits of using optimum RAP-based options and a virgin-material-based WMA case against the baseline virgin material case were also investigated. Results showed benefits of WMA as higher than replacing virgin asphalt with recycled asphalt (25% RAP asphalt base, 15% RAP binder and wearing courses). Land use (19%) and energy consumption (16%) showed the highest reduction, followed by ozone depletion (14%), ionizing radiation (11%), PM (8%), acidification (7%) and global warming potential (6%) across all pavement lifecycle stages and environmental indicators. Similar results were obtained for other scenarios with lesser degrees of reduction, which show the significance of replacing HMA with WMA for real-world projects, specifically in mega road projects in Abu Dhabi and the Middle East towards cutting the significant carbon footprint of asphalt pavements.
AB - Roads account for a major part of energy/resource consumption and emission of GHGs, such as CO2, PM, NOx, O3, etc., due to high demand for virgin materials, specifically in developing regions. The applicability of recycled materials, such as recycled asphalt pavement (RAP) and other alternative approaches for, e.g., warm-mix asphalt (WMA), in developed countries is hindered by project-specific constraints and lack of empirical studies in these regions. Lifecycle assessment studies on the usage of these road options from actual projects in the developing countries can aid decision makers choose sustainable material approaches by providing case study examples as guidelines. To that end, this study analyses environmental in/out-flows for a traditional approach and multiple green approaches (RAP and WMA) for a major highway section in Abu Dhabi through a 30-year (2015–2045) lifecycle approach. Roadworks were modelled in SimaPro according to real-world conditions, and the expected burden mitigation in each stage is calculated. Benefits of using optimum RAP-based options and a virgin-material-based WMA case against the baseline virgin material case were also investigated. Results showed benefits of WMA as higher than replacing virgin asphalt with recycled asphalt (25% RAP asphalt base, 15% RAP binder and wearing courses). Land use (19%) and energy consumption (16%) showed the highest reduction, followed by ozone depletion (14%), ionizing radiation (11%), PM (8%), acidification (7%) and global warming potential (6%) across all pavement lifecycle stages and environmental indicators. Similar results were obtained for other scenarios with lesser degrees of reduction, which show the significance of replacing HMA with WMA for real-world projects, specifically in mega road projects in Abu Dhabi and the Middle East towards cutting the significant carbon footprint of asphalt pavements.
KW - highways
KW - lifecycle analysis
KW - road construction
KW - scenario analyses
KW - warm-mix asphalt
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U2 - 10.3390/civileng3020015
DO - 10.3390/civileng3020015
M3 - Article
AN - SCOPUS:85132431598
SN - 2673-4109
VL - 3
SP - 242
EP - 262
JO - CivilEng
JF - CivilEng
IS - 2
ER -