Tolerances for Placement of Tie Bars in Portland Cement Concrete Pavements

Tie bars provide load transfer along longitudinal joints and prevent lane separation in jointed concrete pavements. Tie bars are normally located within the middle third of the pavement thickness and span the longitudinal joint of two slabs. Tie bars are placed by staking or by using tie bar baskets prior to the placement of the concrete or during paving via automatic inserters. Inspection of South Dakota pavements after construction using ground penetrating radar (GPR) has revealed that many bars were misaligned or missing. More bars were reported missing or misaligned when automatic inserters were used. Many states, including South Dakota, have banned the use of automatic inserters based on a lack of confidence regarding the placement of tie bars. The long-term effect on the pavement from misaligned or missing bars is unknown, but it can be assumed that additional maintenance costs and reduced pavement life are both possible. Developing an understanding of misplaced tie bars and placement tolerances is important to the South Dakota Department of Transportation (SDDOT). The financial impacts of misplaced tie bars are unknown. Misplaced tie bars could be costing the department substantial amounts of money in the long-run if undetected or uncorrected during construction.

• Record URL:
  https://www.mountain-plains.org/research/details.php?id=330
• 

Language

• English

Project

• Status: Completed
• Funding: $150000
• Contract Numbers:

  DTRT12-G-UTC08

• Sponsor Organizations:

  Research and Innovative Technology Administration

  University Transportation Centers Program
  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Managing Organizations:

  Mountain-Plains Consortium

  North Dakota State University
  Fargo, ND  United States  58108
• Project Managers:

  Kline, Robin

• Performing Organizations:

  Dept. of Civil and Environmental Engineering

  South Dakota State University
  Brookings, SD  United States 
• Principal Investigators:

  Wehbe, Nadim

• Start Date: 20120101
• Expected Completion Date: 20190930
• Actual Completion Date: 20200902
• USDOT Program: University Transportation Centers Program
• Source Data: MPC-440

Subject/Index Terms

• TRT Terms: Concrete pavements; Ground penetrating radar; Longitudinal joints; Portland cement concrete; Service life; Tie bars
• Uncontrolled Terms: Misalignments
• Geographic Terms: South Dakota
• Subject Areas: Design; Highways; Pavements;

Filing Info

• Accession Number: 01497112
• Record Type: Research project
• Source Agency: Mountain-Plains Consortium
• Contract Numbers: DTRT12-G-UTC08
• Files: UTC, RiP
• Created Date: Oct 30 2013 1:00AM