As part of its activities, the C.R.O.W working group B 13 on the maintenance of porous asphalt has to examine the durability of porous asphalt surfacings. This contribution deals with various aspects of that important subject: typical deficiences in porous asphalt surfacings, contribution to the structural strength of the pavement, service life under field conditions, development of binder characteristics in time, bond between binder and aggregates, and the frequently observed phenomenon of a porous asphalt wearing course loosening from the underlying asphalt layer. Improving the tack coat may help to reduce this phenomenon. On the other hand, modified bitumens can be used to reduce binder ageing, but observations on road sections have not made it possible to find out whether improving these characteristics results in longer service lives.
Samenvatting