Life Cycle Illustration

The contents of this page illustrate a pavement's life cycle emissions created by the PE-2 estimator tool using data from the observed MDOT projects.

Figure 1: Conceptual Illustration of Pavement Life Cycle outlines the cumulative emissions associated with typical roadway’s life cycle. Emissions outlined by the PE2 Life Cycle Tool include:

  • Construction Emissions
    • Emissions from the manufacturing and processing of virgin and recycled materials
    • Emissions from on-site construction equipment
    • Emissions from hauling equipment hauling materials to and from the project site
    • Upstream Impacts for the manufacturing of the fuel combusted in the construction and hauling equipment
    • Upstream impacts from the manufacturing of equipment being used on site
  • Work Zone Emissions
    • Emissions associated with traffic delay throughout work zone durations
  • Use Phase Emissions
    • Emissions associated with vehicle use of the roadway

To illustrate the information outlined in Figure 1: Conceptual Illustration of Pavement Life Cycle the following example was modeled using the PE2 Life Cycle Tool and the following results were obtained:
1. General Project Information

  • Roadway Speed = 70mph
  • Average Daily Traffic = 8800 vehicles/day
  • Project Length = 10 miles
  • Number of lanes = 4 (Results in 40 lane miles)
2. First intervention strategy
  • Emissions from US-31 HMA Reconstruct (PN50757) were used to account for year 1 initial construction and work zone emissions.
  • The duration of the project was determined to be 197 days
3. Second intervention strategy
  • Emissions from US-31 Over band Crack seal and Micro surface (PN106529) were used to represent the first maintenance.
  • Defined at year 5
4. Third intervention strategy
  • Emissions from M-20 HMA Cold milling and Overlay (PN105611) were used to represent the second maintenance.
  • Defined at year 9
5. Final intervention strategy
  • Emissions from US-41 HMA Reconstruct and Realignment (PN80145) were used to represent the end-of-life.
  • Defined at year 15

Results from the life cycle illustration are outlined in Table 1: Life Cycle Emissions and Figure 2: Life Cycle Emissions. Emissions associated with construction, maintenance and work zones are diminutive compared to emissions associated with vehicle use. Emissions from the use phase can represent 85-95% of the pavement life cycle.

Overall annualized emissions per lane mile is approximately 511.27 MT CO2 Eq/Year

Design downloaded from free website templates.