ABSTRACT
Nowadays porous wearing courses are very popular in the Netherlands*3*. The reason for this is mainly, that they give comforts to the use of the road. They have a high skid resistance, they reduce the noise nuisance, prevent splash and spray water, while aqua-planing in principle is impossible. The minimum thickness of the asphalt structure ZOAB with one layer of coarse mastic asphalt, one layer of drain asphalt and two membranes on orthotropic steel decks amounts 70 mm which results in a weight of about 175 kg/m2. New potyurethane porous wearing course ZOK The recently by Bolidt*4* developed porous wearing course ZOK has a weight of 90 kg/m2 at a thickness of 50 mm. Characteristic of this one layer system is the use of synthetic materials instead of bitumen binders. Bending tests showed a promising flexibility of the wearing course against fatigue. At -20 °C, yielding of the steel plate occurred without cracking of the ZOK. The dynamic stiffness moduli were measured at temperatures between -20 and +60 °C at loading frequencies between 1 to 30 Hz. The results (see Figure 4) showed a relative constant value.
