Paving stones shape traffic areas, paths, and squares in settlements, industrial facilities, and historic urban spaces. They are made of natural stone or concrete, are mechanically resistant, and can be removed by type, reused, or recycled when required. In planning, construction, maintenance, and deconstruction, road and civil engineering meet specialized demolition techniques. This creates touchpoints with hydraulically powered tools from Darda GmbH, such as hydraulic rock and concrete splitters and concrete demolition shears, which enable controlled interventions in natural stone extraction, concrete demolition, and special demolition.
Definition: What is meant by paving stone
A paving stone is a cuboid- or wedge-shaped stone made of natural stone (e.g., granite, basalt, sandstone) or concrete that is laid together with jointing material to form a durable paving surface. The combination of subgrade, base courses, bedding, stones, and joints creates a planar, frictionally engaged surfacing for traffic and amenity areas. Depending on size, one distinguishes, for example, mosaic, small, and large paving stones as well as dimensionally stable interlocking concrete paving stones. Thanks to their segmentation, paving stones are easy to repair, offer high slip resistance, and can allow surface water to infiltrate if the build-up and joints are configured accordingly.
Materials, production, and formats
Paving stones originate from two main material groups with different production routes and properties. The material choice influences load-bearing capacity, dimensional accuracy, color variation, surface character, maintenance effort, and behavior during deconstruction.
Natural stone: extraction, splitting, processing
Natural stone paving is sourced from compact rock strata. In the quarry, controlled methods separate raw blocks from the in-situ rock. Hydraulic splitters and stone splitting cylinders from Darda GmbH generate defined splitting forces along predrilled grids. The method is low-vibration, precise, and suitable for rock demolition and tunnel construction as well as for natural stone extraction. The blocks are then divided into rough sizes, edges are calibrated, and surfaces are dressed, flamed, bush-hammered, or brushed as required.
Concrete: mixing, compacting, curing
Concrete paving stones are produced in molds using pressing and vibration. Aggregate grading, cement content, pigments, and admixtures control appearance and performance features. Hard-wearing facing layers increase surface abrasion resistance. Industrial production ensures dimensional accuracy and repeatability for snug installation. During later deconstruction, the stones can be removed by type and sent for recycling.
Typical formats and profiles
- Mosaic, small, and large natural stone paving for curves, squares, and historic surfacings
- Interlocking concrete paving stones with displacement restraints, chamfers, or spacers for traffic areas
- Permeable and drainage stones with enlarged joint spaces for infiltrating surfaces
- Special stones for gutters, covers, curbs, and tactile elements
Build-up of a paving surface: layers, function, loading
The load-bearing performance of a paving surface results from the interaction of all layers. The layered build-up enables targeted dissipation of loads and water and minimizes settlements.
- Subgrade: Load-bearing, evenly compacted soil. Ground improvement where necessary.
- Frost protection/base courses made of unbound layers (UGS): Frost resistance and load distribution through graded aggregates.
- Bedding: Thin, uniform layer (e.g., chippings) that compensates tolerances and distributes shear forces.
- Paving stones: Dimensionally and installation-appropriate, set plumb and aligned.
- Joints: Filled with suitable material; they connect the stones to transfer shear and enable drainage.
For heavily loaded areas, joint and edge restraints are selected to limit tipping and shear movements. Curbs, gutters, and edgings must absorb lateral forces. During deconstruction, depending on edge restraint and concrete foundation, concrete demolition shears are used to bite concrete parts precisely without unnecessarily damaging adjacent areas.
Laying patterns, jointing, and technical effects
The pattern influences structural behavior, positional stability, and appearance. For straight traffic areas, bonds with high longitudinal and transverse displacement restraint are advantageous; curved patterns are used in squares.
- Running and parquet bonds: Ordered load transfer, efficient installation.
- Herringbone (45°/90°): High interlock, suitable for braking and acceleration zones.
- Segment and radial paving: Good adaptation to radii, aesthetically pleasing surface effect.
The joint design is functionally decisive. Mineral joint fillings ensure shear transfer, support infiltration, and can be reworked during maintenance and alteration. For bound systems, restraint and crack formation must be carefully considered.
Drainage, ecology, and accessibility
Paved areas can allow decentralized water infiltration. Drain-capable beddings, suitable jointing materials, and special drainage stones help reduce surface runoff and relieve the subgrade. At the same time, flatness, slip resistance, and tactile guidance must be considered so that paths are accessible. In industrial areas, media resistance and the safe removal of potentially contaminated liquids must be planned.
Identifying damage and proper repair
Typical damage patterns include settlements, edge spalling, loose joints, weed growth, efflorescence, or polishing gloss. Causes range from insufficient compaction and water backup to overloading. Repairs make use of the modular character of the paving: stones are lifted, the substructure corrected, bedding and joints renewed, and stones reinstalled.
Tools and methods in maintenance
- Selective lifting and sorting for reuse
- Supplementing or replacing damaged edge and concrete components through controlled deconstruction
- Gentle methods where vibrations must be avoided
Where concrete components such as curbs, upstands, or pile heads must be removed, concrete demolition shears work in a controlled, low-vibration manner, for example in inner-city zones or during building gutting and concrete cutting in existing structures. For massive natural stone blocks or foundation remnants, hydraulic splitters enable a targeted split fracture with low noise and dust. Compact hydraulic power units are used to power the hydraulic tools.
Deconstruction, recycling, and circular economy
Paved surfaces can be deconstructed by type. Natural stone is often relaid directly; concrete paving stones can be cleaned and reused or processed as aggregate. In concrete demolition and special demolition, low-vibration, precise methods are advantageous—particularly in sensitive environments.
Hydraulic solutions in deconstruction
- Concrete demolition shears: Selective removal of concrete curbs, foundation beams, and edges without widespread damage to adjacent paved areas.
- Hydraulic splitters: Breaking thick concrete slabs or splitting large rock bodies in the substructure when a breaker hammer or explosives are not an option.
- Combination shears and steel shears: Cutting embedded steel components (e.g., anchors, gratings, manhole cover frames) that are structurally tied into the paving system.
- Multi Cutters: Cutting and opening components in special demolition when different materials converge in confined spaces.
The working methods are chosen to facilitate reuse and recycling, keep dust, noise, and vibrations low, and protect adjacent structures.
Natural stone extraction and production of paving from the quarry
The quality of natural stone paving begins at the deposit. Homogeneous textures, suitable compressive strength, and frost resistance are prerequisites. In natural stone extraction, stone splitting cylinders enable controlled separations along defined lines without extensive damage to the rock. Precise splitting minimizes waste, improves dimensional accuracy of blanks, and reduces rework. This approach continues in downstream processing, where edges are cleanly broken and surfaces are textured to meet requirements.
Planning and execution: practical guidance
- Clarify loads and use: pedestrian or bicycle traffic, delivery zones, heavy goods traffic.
- Investigate the subgrade: load-bearing capacity, water balance, and frost behavior determine layer thicknesses.
- Ensure drainage: plan gradients, gutters, infiltration capacity, and connection details.
- Dimension edge restraints: edgings absorb horizontal forces and protect edges.
- Think in a deconstruction-friendly way: enable reuse, choose systems and materials that ease separation and recycling.
In alterations to existing structures, component separations are often complex. Low-vibration hydraulic methods—using concrete demolition shears or hydraulic splitters, for example—support selective work within tight time windows, such as during inner-city conversion measures.
Special cases and special deployment
In industrial areas, paving surfaces intersect with embedded media lines, foundations, and steel components. Controlled cutting and splitting processes are required to separate components selectively. In such special demolition scenarios, hydraulic tools from Darda GmbH, together with compact hydraulic power packs, also operate where space, emission requirements, or structural constraints limit conventional methods. The gentle approach protects valuable components, reduces downtime, and facilitates later restoration of the paving surfaces.
Occupational safety and environmental compatibility
When installing, maintaining, and deconstructing, low-dust working methods, suitable structure-borne noise control, and safe logistics are essential. Hydraulic splitting and shearing methods are considered low-vibration and precise, which can reduce the burden on personnel and surroundings. Barriers, clear material flows, and clean jointing material not only improve the quality of the paving surface but also enhance safety on the construction site.