Porous asphalt is a material that was introduced in the Netherlands some twenty years ago. Over the past two decades extensive knowledge was amassed about the material technical aspect in particular. However, a lot of supplementary information still has to be acquired. This goes specifically for the maintenance aspect and the development of the draining qualities and the noise reducing qualities in time. Yet on the basis of a cost/benefit analysis, departing from a number of assumptions, the decision was made to use porous asphalt on large parts of the national trunk road system. The benefits result of the augmented traffic safety caused by the draining qualities of porous asphalt and the reducing effect on the number of traffic-jams. The noise reduction benefits, although not quantified, have contributed to this decision. The costs are mainly determined by a lower structural contribution, shortened life span and supplementary maintenance costs. For the years to come research will be aimed particulary at the possibilities for an economical prolongation of the life span and at the quantitative, statistically relaible effects on traffic safety and capacity. The experiences outlined in this publication only apply to the Dutch (a.o. climate) conditions.
Abstract