Longtime Experience with Exposed Aggregate Surfaces in Austria

Exposed aggregate surfaces MA 8 have been used in Austria on a !arge scale since 1990 and have proveu not only noise-reducing but also very skid resistant. On different motorway sections paved with the same quarzitic chippings 4/8 the friction values (Stuttgart friction meter, 60 km/h, with water, with slip) were between 0,70 and 0,80 immediately after construction dropped by 0,10 during the first 3 years to remain at a (very satisfactory) level of 0,60 to 0,70. Friction is very uniform within the sections.