Therefore, in North America, organizations such as AASHTO and FHWA collected large amounts of data about pavement conditions.
Examples of these databases, which are used for pavement design and performance measurement, are the LTPP and AASHO Road Test.
[1] Among the most significant environmental factors are freeze-thaw cycles, maximum and minimum temperature and precipitation.
[8] So, roads exposed to larger number of freeze-thaw cycles and higher precipitation levels deteriorate faster.
[7] Usually larger volumes of traffic and heavier vehicles such as trucks are correlated with faster pavement degradation.
Examples of the factors directly related to management are the type and frequency of maintenance[3] or cleaning and deicing approaches in the winter.
Sometimes these attributes are expressed via an aggregated measure called granular base equivalence (GBE).