When considering core placement, what is an essential factor in determining horizontal placement?

The essential factor in determining horizontal placement of core samples is the offset based on road width. This consideration ensures that the core samples are taken from representative locations across the width of the pavement, which is critical for assessing the overall quality, thickness, and density of the asphalt layer.

When cores are placed without proper consideration of the offset, it may lead to unrepresentative data that could obscure potential issues in the paving process. For instance, if cores are taken only from the center of the road or only on one side, the assessment may miss variations in compaction or thickness that could occur across the total width of the pavement. By focusing on the offset based on road width, it ensures that samples reflect the full profile of the installation, providing a more accurate understanding of the asphalt's performance.

The other factors, while important in the overall context of asphalt paving, do not directly influence the horizontal placement of core samples in the same way. The starting station typically relates to project layout rather than core positioning, the type of asphalt affects performance and application but not placement, and the length of the pavement addresses the extent of the project but is not a direct factor for horizontal placement within the road’s cross-section.