Life Cycle Assessment of Flexible Pavement Construction

Aims: The main objectives of this study are to submit significant contribution to the field of environmental assessment of flexible pavement construction method in Egypt based on a life cycle assessment study. This contribution will be useful in the planning and management of sustainable road construction in Egypt.

Study Design: A comprehensive life cycle assessment (LCA) of asphalt pavements construction methods were conducted including hot mix asphalt (HMA) method through changing the pavement design parameters such as California Bearing Ratio (CBR) and Average Annual Daily Traffic (AADT). A filed study of the construction data of three main roads in Egypt was carried out. Data are used as base for the inventory data and influent parameters in this study.

Place and Duration of Study: Three major high ways in Egypt, Between November 2013 and June 2015.

Methodology: Nine scenarios represent different design parameters of flexible pavement design methods are investigated. The average annual daily traffic are (10,000 – 25,000 – 50,000 – 100,000 – 150,000) vehicles per day with 10% of heavy vehicles, growth factor (Gf) 3% and California bearing ratio CBR (3%, 6%, 10%, 15%).

Results: The results showed that by changing CBR from 3% to 15% for each AADT, noted the environmental effect are decreased by (5 and 40) % due to the improvement in the soil. By increasing AADT from (10,000 to 150,000) veh/day at each CBR value, the environmental impacts are increase by (5 and 25) % due to the increase in traffic volume.

Conclusion: The pavement construction had adverse effect on environmental. The transport of materials used in roads construction produce the most significant environmental impacts. The pavement LCA can help to increase the environmental performance of roads construction and guide authorities towards road sustainability management.