Paving is one of the oldest construction methods for paving squares and streets. Even today, they are still omnipresent, e.g. in the streets of historic old towns. However, paving surfaces are also popular in public areas that need to be redesigned, in private gardens and driveways, on terraces and garden paths, as they can withstand high loads and offer a variety of design options with the choice of material, format and installation pattern.
DIN 18318 VOB C only deals with paving surfaces and slabs that are laid using the unbound construction method. This is considered a standard construction method for paved areas. However, the unbound paving method is often not suitable for today's requirements resulting from road traffic (heavy goods traffic). Ruts, displacement of the paving stones, subsidence, etc. are the result. Unbound joints are also regularly damaged by sweepers and vacuum cleaners. Public areas are therefore primarily designed in bound construction according to RStO (Guidelines for the Standardization of the Superstructure of Traffic Areas). The RStO describe standard construction methods for the reinforcement of traffic areas in public road space, which can also be used for the planning of the superstructure of private paved areas.
Materials: When choosing a paving surface, the planner is not only concerned with design aspects (appearance of the material, paving format, laying pattern, etc.), but also with the material properties and functionality of the paving material, which must meet the usage and load requirements of the respective traffic area. These include, in particular, weather resistance, de-icing salt and abrasion resistance, fracture resistance, slip and slip resistance, but also the cleaning and maintenance effort involved. Natural stone paving is generally much more expensive than concrete block paving. [...]
Image: Natural stone paving - bauwion
Image: Concrete block paving - bauwion
Image: Clinker paving - bauwion
Image: Holzpflaster - bauwion
Source: bauwion
Unbound construction: As a standard construction method for paved surfaces, the unbound construction method has been introduced in DIN 18318 VOB C.
This is the laying of the paving stones in a bedding layer about 3 to 5 cm thick (crushed sand-chippings mixture), underneath which is a coarse-grained base course of a crushed sand-gravel mixture. If the risk of frost is high, an additional frost protection layer underneath the base course is necessary.
The sequence of layers and layer thicknesses of the superstructure (pavement, bedding, base and frost protection layer) are always based on the expected stress.
If it is not sufficiently permeable, the subgrade below is provided with a gradient of at least 2.5 % in order to safely drain water or direct it to a drainage system. All layers must be filter-stable in relation to each other in order to avoid material leaching.
In the case of unbound construction, an edge edging of the surfaces is mandatory.
Image: Construction of unbound construction - bauwion
Usually, the joint filling is also carried out without binders in unbound construction, but when paving private areas, which are often not exposed to high traffic loads, the unbound construction method is often combined with bonded joints. This has the advantage that the joints remain maintenance-free (no washout of the joint material, no joint growth). Since the paving surface has a certain elasticity due to its design, the joint filler must also meet this property. High-strength joint fillers are generally not suitable for unbound construction.
Source: bauwion
