What does VMA stand for in asphalt?
Voids in Mineral Aggregate (VMA) VMA is the volume of intergranular void space between the aggregate particles of a compacted paving mixture.
What is Superpave system?
The Superpave (SUperior PERforming Asphalt PAVEments) system was developed to give highway engineers and contractors the tools they need to design asphalt pavements that will perform better under extremes of temperature and heavy traffic loads.
What is Superpave 19?
Superpave 19.0 Binder course mix for Traffic Category A, B, C, D, and E roads. Superpave 19.0 is similar to the traditional HL 4, HL 8, and (HS) HL 8 mixes according to OPSS 1150. Superpave 25.0 Large stone binder course mixes for use when thicker binder course lifts are required.
Why is VMA important in asphalt?
VMA serving as the air voids among the aggregates is considered as an important parameter used in designing the asphalt mixture. VMA is used to ensure that the binder film thickness is sufficient enough to protect the mixture from the abrasive action of tires and water (Moghaddam et al., 2015b).
What happens if VMA is low?
When VMA is lowered, you lower the asphalt binder content for a given air void level (typically 4.0 percent for Superpave mix design). And when you lower the asphalt content, the mix becomes more economical but also less durable.
What is dust to binder ratio?
During design, mixtures that are above the maximum density line at the 2.36-mm (for 19-mm or smaller mixtures) or 4.75-mm (for 25-mm or larger mixtures) critical sieve should have a dust-to-binder ratio of no more than 1.4.
What is 19mm asphalt?
Asphalt Paving ‐ 19mm Binder Course 19mm Binder Course is applied in one layer, is as strong as regular base and has a sufficient amount of liquid asphalt to roll into a very durable surface. The difference is that the texture is coarser than 9.5mm Wearing Course.
What is the Superpave 12.5 FC2?
Superpave 12.5 FC2 Surface course mix for use on Traffic Category D and E roads that provides superior rutting resistance and skid resistance through aggregate selection. Superpave 12.5 FC2 is similar to the traditional DFC mix according to OPSS 1150.
What is HL8 asphalt?
Driveway Paving, Commercial Patching & More HL3 – This commercial grade asphalt is used in situations where a more durable surface is needed. HL8 – Base asphalt is used for multi layered applications.
Who can use pavement interactive?
With its broad coverage, Pavement Interactive can be helpful to a wide range of potential users, including engineers, technicians, equipment operators, inspectors, managers, researchers, and students as well as the general public. An overview of the history and basic concepts involved in road pavements.
What is progresspavement interactive?
Pavement Interactive is a free online knowledge base for the paving industry. The site is a repository for encyclopedic articles, news, and information on all topics related to pavements. It serves as a resource for contractors, government agencies, consultants, and others in the transportation infrastructure industry.
What is the difference between VMA and VFA?
VMA is defined as the sum of the volumes of the air voids and the unabsorbed binder in the compacted specimen. VFA is the percentage of VMA containing asphalt binder. It is widely accepted that these volumetric properties are useful in predicting hot-mix asphalt pavement performance.
Why is quality important in paving?
Quality has become one of the most important consumer decision factors in the selecting among competing products and services. When designing pavements there are three fundamental external design parameters to consider. The combined effects of traffic loading and the environment will cause every pavement to deteriorate over time.