What is the relationship between RAP percentage and total aggregate weight?

The understanding of the relationship between Reclaimed Asphalt Pavement (RAP) percentage and total aggregate weight is crucial in asphalt paving. When considering the options available, the correct answer highlights a key guideline in the use of RAP in asphalt mixes.

RAP is incorporated into the mix to enhance both environmental sustainability and cost-effectiveness. In many specifications, the maximum RAP content is set at 20% by weight of the total aggregate. This limit is in place to ensure that the performance and quality of the asphalt mixture are maintained, as too high a percentage of RAP could degrade the properties of the asphalt, leading to issues such as insufficient binding or premature failure.

This 20% maximum is often a default referenced in various guidelines, ensuring that while the benefits of using recycled materials are harnessed, the integrity of the end product remains paramount. This promotes a balance between utilizing existing materials and maintaining performance standards necessary for pavement longevity.