Reducing Costs in Full Depth Reclamation

Details

• Creators:
  Kim, Jinho ; Sebesta, Stephen ; Choi, Kunhee ; Taylor, Ross
• Corporate Creators:
  Texas A&M Transportation Institute
• Corporate Contributors:
  Texas Department of Transportation. Research and Technology Implementation Office ; United States. Department of Transportation. Federal Highway Administration
• Subject/TRT Terms:
  CA4PRS Cement Construction Projects Costs Emulsified Asphalt Foamed Asphalt Full-depth Reclamation Performance Project Management Traffic Control
• Publication/ Report Number:
  FHWA/TX-25/0-7143-R1
• Resource Type:
  Tech Report
• Geographical Coverage:
  United States ; Texas
• Edition:
  September 2022–October 2025
• Corporate Publisher:
  Texas A&M Transportation Institute
• Abstract:
  Full depth reclamation (FDR) using emulsified asphalt or foamed asphalt continues to grow in usage throughout Texas. These mixtures typically use a cement additive in the mix design. The cement additive reportedly contributes to early strength gain, which can be particularly important for projects that require daily opening to heavy traffic. However, not all construction projects require daily opening to traffic, and some materials may provide adequate performance without the cement additive. Additionally, with potential cement supply shortages, design and construction of FDR layers using only asphalt treatments could save materials cost, reduce schedule risk, and increase daily productivity since one less step would be required in the treatment process. This project determined that without the cement additive, an additional three to four hours cure time could be required prior to opening to traffic. FDR mixes without the additive may be able to obtain similar strength and performance properties as long as they stay dry, but most common Texas materials for FDR require the cement additive to meet moisture conditioned strength requirements. If sourcing cement proves difficult, this project showed lime could be substituted 1:1 for the cement additive, although mixes with lime additive were less reliable in meeting moisture susceptibility criteria compared to mixes that used cement as the additive. In practice, emulsified or foamed asphalt-treated FDR mixes without additive could provide material cost savings, faster production, and user-delay savings, with the potential tradeoff of increased long-term performance risks due to their higher level of moisture susceptibility. Thus, no additive mixes are best considered on a case-by-case basis for low-risk areas, projects with logistical challenges for sourcing additives, or for projects where simply upgrading material properties is desired.
• Format:
  PDF
• Funding:
  0-7143
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha-512:ab8e32a0ee8f1f59b7bea23853993322aeec550edc9e0772b0b4a5a73ed2b5bf49c2e83e49a5badacb5e60496ebab4dd7a445999faab338f6987dedd4cc1f857
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/88499/dot_88499_DS1.pdf
• File Type:
  [PDF - 11.17 MB ]