What is the function of a moisture barrier in asphalt applications?

The function of a moisture barrier in asphalt applications is primarily to prevent moisture penetration and subsequent damage to the pavement structure. When moisture penetrates through the asphalt surface into the underlying layers, it can lead to several issues such as erosion of the base materials, increased deformations, and ultimately, structural failure of the pavement. A moisture barrier helps to create a protective layer that keeps water out, thereby maintaining the integrity and longevity of the asphalt pavement.

The barriers can be particularly significant in areas with high water tables or in climates where freeze-thaw cycles are common, as these conditions can exacerbate the damage caused by moisture intrusion. By mitigating these issues, a moisture barrier directly contributes to the performance and durability of the pavement, ensuring it remains in good condition for a longer period.

While improving aesthetic quality, enhancing durability, and reducing costs are important aspects of pavement construction and maintenance, they are not the primary roles of a moisture barrier. These factors may influence the overall choice of materials and methods but do not define the specific function of a moisture barrier in protecting against moisture-related damage.