During core sampling, how should the barrel of the core drill be positioned?

When performing core sampling, positioning the barrel of the core drill perpendicular to the pavement is crucial for obtaining accurate and representative samples. This vertical alignment ensures that the cores reflect the true thickness and material properties of the pavement layers.

If the core drill were positioned at an angle, it could result in skewed samples that do not accurately represent the pavement's structural integrity or thickness. This misalignment can lead to difficulties in analyzing the core and may compromise the data gathered for quality control or pavement assessment purposes. Therefore, adhering to the practice of maintaining a perpendicular orientation helps to ensure consistency and reliability in core sampling procedures.