Draining function of porous asphalt during snowmelt and temporary freezing

Urban runoff creates problems with flooding and pollution of receiving waters. Furthermore, cold climate conditions have a degenerating effect on stormwater systems and road constructions. Porous asphalt has been used as a wearing course on highways and in porous pavement constructions all around the world. The main focus of this study was to evaluate the function of porous asphalt in cold climates. Measurements of the draining function of porous asphalt were carried out in a climate room with adjustable temperature in the range -10%C to +20%C. At freezing point, the infiltration capacity of porous asphalt was approximately 50% of the infiltration capacity at +20%C. When the porous asphalt was exposed to alternating melting and freezing during 2 days, conditions similar to the snowmelt period, the infiltration capacity was reduced by approximately 90%. Based on the results of this study and previous studies, the infiltration capacity of porous asphalt was estimated to be 1-5 mm/min for snowmelt conditions.