PVA fiber reinforced shotcrete for rehabilitation and preventative maintenance of aging culverts.

Details

• Creators:
  Davidson, James S. ; Kang, Junsuk ; Grimes, Thomas C. ; Farrell, Jim ; Vaidya, Uday K. ; Pillay, Brian ; Thattaiparthasarat, Balaji
• Corporate Creators:
  Auburn University. Dept. of Civil Engineering ; Shelby County (Ala.). Highway Dept. ; Blastcrete Equipment Company ; University of Alabama at Birmingham. Dept. of Civil, Construction, and Environmental Engineering
• Subject/TRT Terms:
  • Organic compounds
  • Alcohols
  • Fiber reinforced concrete
  • Shotcrete
  • Culverts
  • Maintenance practices
• Publication/ Report Number:
  Project 930-657
• Resource Type:
  Tech Report
• Geographical Coverage:
  Alabama
• Edition:
  Final report; Dec. 2008
• Corporate Publisher:
  Alabama. Dept. of Transportation
• NTL Classification:
  NTL-HIGHWAY/ROAD TRANSPORTATION-Pavement Management and Performance ; NTL-HIGHWAY/ROAD TRANSPORTATION-Materials ; NTL-HIGHWAY/ROAD TRANSPORTATION-Construction and Maintenance
• Abstract:
  The goal of this project was to investigate the potential for using PVA (polyvinyl alcohol) fiber ; reinforced mortar for the rehabilitation and preventative maintenance of aging metal highway ; drainage culverts using a spray-on liner application approach. The interest and impetus for the ; investigation resulted from prior work of the investigators with county engineers that pointed ; towards the need for new cost-saving technologies for rehabilitating deteriorated metal highway ; drainage culverts that preclude the need to close the roadway and excavate the existing structure. ; The investigation was conducted by a team comprised of the polymer materials expertise of the ; UAB Department of Materials Sciences and Engineering, the civil/structural engineering ; expertise of the Auburn University Department of Civil Engineering, and the concrete ; application solutions expertise of Blastcrete Equipment Company, Inc. The investigation ; focused on the strength and toughness advantages provided by reinforcing spray-on concrete ; (shotcrete) with high performance PVA fibers. Tasks included developing and optimizing the ; material concept, laboratory strength testing, and developing engineering design methodology. ; Full scale demonstrations of the concept were accomplished by Blastcrete Equipment Company, ; Inc., at their facility in Anniston Alabama. ; The laboratory-scale component of the investigation verified the significant tensile strength, ; ductility, and strain-hardening characteristics that have been presented by others for PVA-ECC ; (engineered cementitous composite). However, achieving the performance demonstrated by ; others proved to be challenging, even in a controlled laboratory environment. Ductility and ; strength performance depends upon using very precise and specific constituents, including fine ; silica sand with average particle diameter of 110 μm or less, and proprietary admixtures required ; to prevent clumping of the fibers. Also, since PVA fibers are hydrophilic, achieving proper ; water content proved challenging. These challenges were amplified when developing a ; methodology for pumping and spraying the PVA reinforced mortar on the inside of a corrugated ; steel pipe. Many iterations were required to balance the challenges of pumpability and ; sprayability with the requirement that the liner material must readily adhere to the obvert of the ; metal pipe. After successfully lining a 48 inch pipe, a three-point bending test was conducted to ; illustrate the strength and stiffness enhancement provided by the liner. Finally, an analytical ; approach was derived for designing the required liner thickness, and practical field ; implementation challenges were outlined. ; Overall, it was concluded that the approach offers great potential as a solution to the metal ; culvert deterioration problem. PVA-ECC offers intriguing and unique characteristics that would ; minimize the required liner thickness while providing the tension strength, rigidity and ductility ; required. It was recommended that the next step be to demonstrate that that a uniform ; structurally sound liner can be applied under field conditions. Additional recommendations ; included to (1) develop field construction guidelines, (2) investigate long-term stability issues to ; ensure stable strength over the service life of the culvert, and (3) refine and validate engineering ; and design methodology through controlled laboratory testing.
  More +
• Format:
  PDF
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/17333/dot_17333_DS1.pdf
• File Type:
  [PDF - 3.17 MB]
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha256:5d8a3c20bc6ffa70291e8d6a1e2c6f4e0082cc4516df5e282ccce1654faea31b