What is the purpose of using cooling agents like dry ice and liquid nitrogen in pavement coring?

The purpose of using cooling agents like dry ice and liquid nitrogen in pavement coring is to prevent damage to the sample during the coring process. When cutting or drilling through asphalt, the heat generated can cause the material to soften or degrade, which negatively impacts the integrity of the core sample. By applying cooling agents, the temperature of the material is effectively lowered, minimizing thermal degradation and preserving the sample’s properties. This preservation is crucial for accurate testing and analysis later on, ensuring that the core represents the original material conditions as closely as possible.

Other potential benefits of cooling agents, such as providing lubrication or cooling the pavement for traffic opening, do not align with the primary objective of maintaining sample integrity during the coring process.