joint quality is compared with regard
to the ‘‘center’’ of the pavement mat (60 right of joint). Field densities and permeability test were made.
Cores were obtained for subsequent lab permeability, density and indirect tensile (IDT) strength testing.
Asphalt content and gradations were also obtained to determine the joint segregation.
In general, this study found that methods providing the most reliable measurements of joint quality are
the AASHTO T166, AASHTO T331 (CoreLok) density tests and the permeability test by Karol-Warner Permeameter.
The minimum required joint density for quality control should be around 90.0% and 88.5% of
theoretical maximum density based on the AASHTO T166 and AASHTO T331 method respectively. Based
on various mix design and longitudinal joint construction methods, the joints show differences in asphalt
content and level of segregation. Results of this study indicate that poor quality of longitudinal joint
should be a combination of segregation, asphalt content variation and insufficient density.