The European standard EN 12697-40 “In-Situ drain-ability” has been transposed into Swiss national standards. It turns out that the new drain-ability measuring method for PA pavements includes several modifications as compared to the replaced Swiss method and the results cannot be compared.
The old Swiss specifications concerning the draining ability of PA pavements is obsolete, the definition of new specifications is required.
This project will enable the IMP laboratory to define new drainability standards for porous asphalt pavements in conformity with EN 12697-40.
In the project 12 road sections were selected that offer a varied sample of porous asphalt concrete (1 x PA4, 4 x PA8, 7 x PA11). The most interesting parameters are the size of the biggest grain, void content and thickness of the layer (the case of bi-layer coatings must be special reflection). Insofar as the permeameter Yverdon ignores the influence of the water temperature, the choice of the date of the test depending on the temperature conditions also seems essential.
Results allow to establish equivalent drainability values of PA pavements. This in turn will lead to a National Annex and, possibly, to a technical recommendation.