New guidelines for the standardization of pavement structures 1986 edition (RStO 1986) – Comparative study at European level

The new standardization guidelines RStO 86 contain rules for the surfacing of roads and other trafficked areas with bituminous, concrete or block pavements, for fully cement-bound pavements as well as for cycle tracks and footpaths. Six pavement construction classes are distinguished, depending on traffic loading. For determining the construction class, it is necessary to determine the traffic loading number VB, which takes account of, among other parameters, a future traffic volume, generally ten years after opening of the road to traffic. The standardized pavement structure comprises the entire pavement down to formation level. Local conditions are more fully taken into account in determining the thickness of the frost-proof pavement layers. In construction class II, the thickness of the concrete slab is generally increased by 2 cm to 22 cm. In construction class I, the slab thickness may likewise be increased by 2 cm to 24 cm, particularly to cope with conditions on very heavily loaded road sections. The rules given in RStO 86 are applicable only to plain (unreinforced) concrete. They do, however, presuppose the installation of dowel bars in the transverse joints and tie bars in the longitudinal joints. This conforms to the design principles adopted in several European countries. Sub-bases are - viewed in a Europe-wide context - chiefly of cement-bound construction; in a few cases this is employed in com~ination with bituminous intermediate layers. The "fully cement-bound pavement" is included for the first time in the standardization guidelines. However, the various forms of construction have not yet been comprehensively tried out. In all European countries where concrete roads are built, the harmless discharge of water from the interfacial plane between slab and sub-base is considered to be important. A number of drainage systems are currently being tested.