An opening after breakthrough is a precisely produced passage through concrete, masonry, rock, or steel structures—such as a wall opening, ceiling opening, or an opening in technical structures. In planning, deconstruction, and fit-out it connects the structural system, finishing trades, and construction workflow. Especially in existing buildings, a low-vibration, controlled approach is essential. Tools such as hydraulic rock and concrete splitters, concrete pulverizers, as well as suitable compact hydraulic power units from Darda GmbH are established for this because they remove material selectively, expose reinforcement, and precisely adjust opening geometries.
Definition: What is an opening after breakthrough
An opening after breakthrough is a deliberately constructed opening in load-bearing or non-load-bearing structural elements (wall, slab, foundation, column) or in rock to enable functions such as doors, shafts, service penetrations, ventilation ducts, or an escape route. It is created by methods such as core drilling, sawing, hydraulic splitting, or mechanical crushing and must meet structural, building-physics, and use-specific requirements (load-bearing capacity, fire protection, sound insulation, watertightness). In deconstruction, openings after breakthrough are often prepared, enlarged, or re-profiled, for example with concrete pulverizers or rock and concrete splitters that are operated with power units from Darda GmbH.
Planning and design of openings after breakthrough
Proper planning begins with determining the structural system, reinforcement layout, and the required clear dimensions. Edge distances, load transfer, fire protection, moisture protection, and the vibration sensitivity of the surroundings determine the method. Depending on element thickness and material, preparatory separation cuts, core drillings, or split-hole drilling may be necessary before the opening is created and finished by post-processing.
Typical geometries and dimensions
The spectrum ranges from small service penetrations and door and window openings up to large-format ceiling openings. While round openings are often core drilled, combinations of sawing, splitting, and crushing are suitable for rectangular or large openings. Concrete pulverizers enable clean edges and controlled material removal, especially for subsequent adjustments.
Effects on the structure and serviceability
Openings after breakthrough change load paths and cross-sections. Interventions in load-bearing elements are relevant to structural design and generally require coordinated verification. Temporary shoring, built-in components (lintels, frames), and a careful work sequence ensure load-bearing capacity and serviceability. When enlarging openings, hydraulic splitting with rock and concrete splitters from Darda GmbH can minimize vibrations and protect sensitive existing components.
Methods of execution: low-vibration and precise
The choice of method depends on material, element thickness, reinforcement ratio, available space, and permissible emissions (noise, dust, water, vibrations). Combined approaches are common to achieve the geometry, surface quality, and schedule targets.
Hydraulic splitting with rock and concrete splitters
Rock and concrete splitters act from the inside in a controlled manner. After drilling boreholes, they generate splitting forces that separate the concrete without impact and with very low vibration. Advantages include low noise exposure, good control of crack propagation, and suitability for thick elements, foundations, or highly reinforced zones. In combination with power units from Darda GmbH they are established in tight existing buildings and sensitive areas such as hospitals or laboratories.
Selective removal and edge profiling with concrete pulverizers
Concrete pulverizers enable targeted nibbling and crushing of concrete, exposing reinforcement as well as precise reworking of opening edges. They are ideal for door and window openings, enlarging ceiling openings, or removing residual webs after separation cuts. The gentle material removal supports clean fit-up for built-in components and fire stop (sealing) systems.
Combination shears, Multi Cutters, and steel shears for reinforcement and inserts
Reinforcing steels, sections, and embedded parts can be cut selectively with combination shears, Multi Cutters, or steel shears. This produces free opening edges without obstructive steel parts that would hinder installing frames, fire protection systems, or services. The tools integrate into the hydraulic equipment fleet of Darda GmbH and allow short cycle times in confined spaces.
Tank cutters for openings in steel vessels
In industrial plants an opening after breakthrough is often required in shell plates or cladding sheets, for example for access, nozzles, or dismantling sections. Tank cutters enable reproducible cut edges and circular openings in steel that can subsequently be safely lined or closed.
Fields of application: from concrete demolition to tunnel construction
Openings after breakthrough are central in many disciplines. The methods and tools of Darda GmbH cover the breadth of applications in different environments.
Concrete demolition and special demolition
In selective deconstruction, openings are created for material removal, equipment access, or new routes. Concrete pulverizers and rock and concrete splitters enable low-emission execution that protects adjacent areas and improves the sorting purity of the demolition material.
Building gutting and cutting
In building gutting, precise service penetrations, new door passages, and shafts must be produced. Here, hydraulic demolition shears score with controlled removal without impact, while shears cut the remaining reinforcement. The coordinated switch between separation cut, splitting process, and shear work shortens the construction time.
Rock excavation and tunnel construction
In rock engineering, openings after breakthrough are created as niches, cable crossovers, or benches. Rock wedge splitters from Darda GmbH produce low-vibration openings even in hard rock, which offers advantages over blasting technology in urban tunnel projects.
Natural stone extraction
When loosening raw blocks and creating transport openings, hydraulic splitting systems are gentle on the material. This produces defined separation planes from which precise openings can subsequently be worked out.
Selection criteria for the appropriate method
The decision between core drilling, sawing, splitting, or crushing depends on several influencing factors. A structured assessment prevents detours and rework.
- Material and reinforcement ratio (C-concrete, masonry, rock, steel-composite)
- Element thickness, geometry, and required edge quality
- Permissible emissions: noise, dust, water, vibrations
- Accessibility, working space, horizontal/vertical orientation
- Safety requirements and sensitivity of the surroundings
- Follow-on trades: fire protection, waterproofing, installation frames, building services
- Schedule window and equipment deployment (power units, power supply)
Practical guide: step by step to the opening after breakthrough
- As-built assessment: drawings, detection of utilities/reinforcement, material testing.
- Structural analysis and approval; if necessary, provide temporary shoring.
- Define geometry, mark layout lines, and create a protection and dust concept.
- Preparatory measures: separation cuts, core drilling, or split-hole drilling.
- Execute the main method: hydraulic splitting, crushing with concrete pulverizers, or shear work on reinforcement.
- Remove/transport out the components, source-separated sorting, and disposal.
- Post-processing: profile edges, achieve tolerances, smooth surfaces.
- Install built-in components: frames, lintels, fire protection and waterproofing systems.
- Quality control, documentation, release for follow-on trades.
Occupational safety, emissions, and site organization
Occupational safety and emissions control are integral parts of execution. The goal is safe, clean, and repeatable production that protects people and the environment. Legal requirements are country-specific; measures should always be coordinated with the parties involved.
Low-emission execution
Hydraulic splitting and shear methods are low-vibration and comparatively quiet. Wet cutting or localized water wetting reduces dust; catch trays and extraction prevent uncontrolled release of slurry. In sensitive areas, noise-control time windows, protective hoods, and dust locks must be planned.
Safety with hydraulic systems
Power units, hoses, and couplings must be checked before use. Secure pinch and shear points, fix components to prevent falling, and establish safe standing areas. Operator qualification, the correct tool size, and defined pressure stages ensure repeatable results.
Quality assurance, tolerances, and post-processing
Opening dimensions, plumb and alignment accuracy, edge quality, and the integrity of adjacent components must be documented. Small dimensional corrections are efficiently achieved with concrete pulverizers, while Multi Cutters remove inserts. Finally, fire collars, fire stop (sealing), or waterproofing are installed and inspected.
Cost and schedule control
Productivity and plan stability increase with clear equipment selection, short setup times, and suitable energy supply. High-performance power units from Darda GmbH, good accessibility, and coordinated material haulage logistics minimize downtime. Wear parts, water and power demand, as well as disposal routes should be calculated early.
Legal and normative aspects in outline
For openings after breakthrough in load-bearing elements, engineering approvals and, where applicable, permits are generally required. Fire protection, building acoustics, and waterproofing must be solved project-specifically. The notes are general in nature and do not replace a case-by-case review or binding advice.
Terms and distinctions in practical use
Planned openings are considered openings after breakthrough, whereas unintended voids or defects are not. Core drilling describes a round opening produced with a core bit; sawing refers to the linear separation cut. Hydraulic splitting creates separating cracks through controlled splitting forces. Selective nibbling with shears serves gentle material removal, for example when re-profiling an opening edge.