NETC 99-2 Evaluation of Asphaltic Plug Joints
Funding Source: New England Transportation Consortium (NETC)
ATMC Materials Lab Involvement: Principle Investigator
End Date: November 30th, 2005
Summary:
Asphaltic Plug Joints (APJs) are flexible asphalt segments that span between the bridge deck and abutment, serving as expansion joints. The advantages of using APJs are that they are quick and easy to install, they are easily repaired, they are not prone to snow damage, they may be cold milled when the road is resurfaced, and they are relatively inexpensive. The disadvantages of using APJs are that the performance of the materials is mainly a function of temperature - they are soft at warm temperatures and stiff at cold temperatures. At cold temperatures they may become brittle, lose ductility, and crack. These cracks cause leaks and debond at the plug joint-pavement interface. At warm temperatures they may rut.
APJs were introduced to New England in the early 1990’s. Consequently, many of these APJs are at the end of their projected service life. To maximize the effectiveness of the APJs in future use, research was needed to evaluate the performance and characteristics over time of asphaltic expansion joints under the extreme temperature variations and winter maintenance in New England. The main goal of this research was to develop uniform guidelines for the use of asphaltic joints in New England.
The objectives of this research project were:
- To evaluate the overall cost, including periodic maintenance, of asphaltic plug joints.
- To identify APJs average useful life span.
- To identify flaws in installation and maintenance methods which could hinder maximum performance.
- To establish recommendations and limitations regarding expansions, skew, thermal limits, etc.
- To identify possible reasons for failure.
- To develop a specification and design/repair guidelines as well as methods for quality control for use by State Highway Departments.
For more information of this project, including a PDF version of the final report, please visit the New England Transportation Consortium website.
