What principle applies when determining the lift thickness in asphalt reconstruction after trenching?

Determining the lift thickness in asphalt reconstruction after trenching is essential for ensuring proper pavement performance and durability. The correct choice indicates that the thickness may be decreased only if necessary for compaction. This approach is important because during reconstruction, the circumstances surrounding the trench may require adjustments to the lift thickness to accommodate effective compaction and to ensure a stable surface.

Reducing thickness in situations where excessive lift heights may lead to difficulties in achieving proper compaction is key. Effective compaction is crucial, as it directly impacts the structural integrity and longevity of the pavement. If the lift is too thick, it may not compact properly, leading to issues such as voids, reduced strength, and premature failure. Therefore, decreasing the lift thickness when necessary for achieving optimal compaction is a best practice in asphalt reconstruction.

The other choices do not align with best practices in pavement reconstruction. Increasing thickness without consideration is not practical or beneficial, and maintaining equal thickness to the original pavement might not account for factors like subsurface conditions. Ensuring constant thickness regardless of conditions also fails to recognize the necessity of adapting to site-specific challenges, which can lead to inadequate performance.