Equivalent single axle loads (ESALs) are used to determine the pavement damage done by each vehicle type compared to the damage caused by an 18,000-pound axle load. For example, passenger cars have a vehicle load factor of 0.0004 (it takes 2,500 cars to equal one ESAL) while a fully loaded fire truck can be as many as 10 ESALs. Once the traffic loading is calculated, paver thickness and aspect ratio must be selected to maximize performance and durability. The heavier the expected traffic, the thicker the paver needs to be to prevent rotation. There are two thicknesses of paver used for vehicular traffic: 80 mm and 100 mm. The 80 mm thickness is suitable for local roads, commercial roads and minor collector roads with up to an expected 1,000,000 ESALs over their lifetimes.The 100 mm thickness is suitable for major collector and arterial roads with up to an expected 9,000,000 ESALs over their lifetimes. At 100 mm thick, the BlackTop Enduro is suitable for all these categories: local roads, commercial roads, minor collector roads, major collector roads and arterial roads.
Aspect ratio is length of the paver divided by its thickness and is used to ensure that pavers will provide proper rotational interlock and cannot be rotated out of place from point loads. Pavers for vehicular applications should have a maximum aspect ratio of 3:1. The BlackTop Enduro comes in well under this at 2:1.
Plan ratio is length of the paver divided by its width. Paver systems with frequent heavy vehicular loads should have a plan ratio of 2:1 and a herringbone laying pattern which provides the best geometry for creating horizontal interlock. The plan ratio of the BlackTop Enduro is 2:1.
