Quality Assurance Quality has become one of the most important consumer decision factors in the selection among competing products and services. This is true not only for individual consumers but also for large corporations, government organizations and the taxpaying...
Specifications Specifications are used (1) to convey information concerning desired products from a buyer to a seller or potential seller, (2) as a basis for competitive bidding for the delivery of products, and (3) to measure compliance to contracts. Typically, four...
Segregation and Temperature Differentials Segregation and temperature differentials are construction-related HMA pavement problems that can lead to early pavement failure. Washington State has been a leader in researching, identifying and combating these problems....
Compaction Compaction is the process by which the volume of air in an HMA mixture is reduced by using external forces to reorient the constituent aggregate particles into a more closely spaced arrangement. This reduction of air volume in a mixture produces a...
Alligator (Fatigue) Cracking A series of interconnected cracks caused by fatigue failure of the HMA surface under repeated traffic loading. As the number and magnitude of loads becomes too great, longitudinal cracks begin to form (usually in the wheelpaths). After...
