Under what condition should you test overbuild for density?

Testing for density of overbuild is crucial as it ensures the quality and compaction of the asphalt layer applied. When the overbuild is greater than one inch, it indicates that there is enough material laid down that can potentially lead to inconsistent compaction and density issues.

A layer that exceeds one inch is significant, as it typically requires a more thorough assessment to ensure that the asphalt has been compacted properly to prevent future issues such as rutting or deformation. At this thickness, it is critical to confirm that the density meets specified requirements to maintain the longevity and durability of the pavement structure.

In contrast, testing for density at less than one inch may not present the same concerns, as such a thin layer has less material volume, which often results in more uniform compaction from the compaction equipment used. Similarly, while one inch may serve as an indicator, it's the condition of being greater than one inch that necessitates testing to verify that the density is sufficient for effective pavement performance. Testing above two inches would typically reflect similar principles but is still adequately covered by testing at greater than one inch. Thus, the emphasis on overbuild greater than one inch effectively captures the need for diligence in ensuring quality asphalt paving.