Granular base equivalency or granular base equivalence (GBE) is a measure of total pavement thickness.[1][2] Since pavement is composed of multiple layers with different physical properties, its total thickness is measured by GBE. GBE translates the thickness of different road layers to a number using a set of coefficients. So, to calculate the GBE, the depth of each layer should be multiplied by the granular equivalency factor for the material in that layer. In the next step the sum of the converted layer thicknesses is calculated.[2] This sum is called granular base equivalency, which is a popular and important measure in pavement design and pavement performance modeling.[3][4][5]
^ abHaas, R., and Kazmierowski, T. 1996. TAC's New Management Design and Management Guide. Transportation Association of Canada (TAC), Ottawa.
^Piryonesi, S. M.; El-Diraby, T. E. (2020) [Published online: December 21, 2019]. "Data Analytics in Asset Management: Cost-Effective Prediction of the Pavement Condition Index". Journal of Infrastructure Systems. 26 (1). doi:10.1061/(ASCE)IS.1943-555X.0000512. S2CID213782055.