Project status
Completed
Start date: 11/01/05
End date: 05/31/07
Researcher(s)
Principal investigators:
- Chris Williams | 515-294-4419 | rwilliam@iastate.edu (project list)
Co-principal investigators:
- Halil Ceylan | 515-294-8051 | hceylan@iastate.edu (project list)
- Kasthurirangan Gopalakrishnan | 515-294-3044 | rangan@iastate.edu (project list)
Student researcher:
About the research
Density is an important component of hot-mix asphalt (HMA) pavement quality and long-term performance. Insufficient density of an in-place HMA pavement is the most frequently cited construction-related performance problem.
This study evaluated the use of electromagnetic gauges to nondestructively determine densities. Field and laboratory measurements were taken with two electromagnetic gauges—a PaveTracker and a Pavement Quality Indicator (PQI). Test data were collected in the field during and after paving operations and also in a laboratory on field mixes compacted in the lab.
This study revealed that several mix- and project-specific factors affect electromagnetic gauge readings. Consequently, the implementation of these gauges will likely need to be done utilizing a test strip on a project- and mix-specific basis to appropriately identify an adjustment factor for the specific electromagnetic gauge being used for quality control and quality assurance (QC/QA) testing. The substantial reduction in testing time that results from employing electromagnetic gauges rather than coring makes it possible for more readings to be used in the QC/QA process with real-time information without increasing the testing costs.
Publications
Report: Investigation of Electromagnetic Gauges for Determining In-Place HMA Density (1.7 mb pdf) May 2007
Tech transfer summary: Testing HMA Density with Electromagnetic Gauges (82 kb pdf) May 2007
Sponsor(s)/partner(s)
Sponsor(s): Iowa Department of Transportation