A sample cut from the compacted pavement with a water-cooled diamond core bit, commonly 4 or 6 inches in diameter. The lab measures its thickness and bulk specific gravity and divides by Gmm to get in-place density, which on many contracts is the number that sets pay. Core locations are picked at random by the agency, and the holes are cleaned, tacked and filled with compacted mix.
State's pulling cores at stations 112 and 118 tomorrow, so get that last pull rolled out before anybody goes home.
Cores are cut after the mat has fully cooled, usually the next day, because a warm core distorts and gives a false bulk gravity.
Also heard as
- core sample
- plug
Related terms
Density
How tightly a compacted asphalt layer is packed, reported as a percentage of its maximum theoretical density.
Nuclear gauge
A portable instrument with a radioactive source that estimates asphalt density in about a minute without cutting a core.
Joint density
The density measured at a longitudinal joint, often specified separately because joints compact poorly.
Pay factor
A multiplier applied to the contract price for a lot of asphalt based on its test results.
Same word, different worlds
The central glass region of an optical fiber where the light actually travels.
Printed Circuit BoardsFully cured laminate with copper on both sides, etched into inner layers and bonded with prepreg into a multilayer.
Concrete & CementA cylinder of hardened concrete drilled out of a structure to test its strength or inspect its condition.
NonwovensTube, usually paperboard, on which nonwoven fabric is wound to make a roll.