The term load transfer describes the path along which actions such as self-weight, live loads, wind, vibrations, and thermal stresses are guided through a structure and discharged into the ground via supports. In concrete demolition and specialized deconstruction, a precise understanding of the load path is crucial to unload components in a controlled manner, correctly assess reserve capacity, and avoid unintended redistributions. Tools such as concrete pulverizers or rock and concrete splitters, along with complementary hydraulic power units from Darda GmbH, enable incremental, low-vibration removal—provided the load path is properly secured before each cutting or splitting operation.
Definition: What is meant by load transfer
Load transfer is the orderly transmission of internal forces and moments from the point of load application through load-bearing members (e.g., slabs, beams, walls, columns, bracing) to the supports and foundations. Characteristic demands such as axial forces (tension/compression), bending moments, shear, and torsion arise in the process. The load path can be considered locally (e.g., within a single beam span) or globally (entire structure) and changes as soon as structural members are removed, weakened, or separated. During deconstruction, controlled unloading and shoring of loads are therefore central to ensure safe, predictable redistribution and to prevent progressive failure mechanisms.
Importance of load transfer in concrete demolition and specialized deconstruction
In selective deconstruction, load transfer dictates the sequence of cutting and dismantling steps, the choice of temporary supports, and the appropriate processing methods. Components are first unloaded, for example by shoring, relief cuts, or targeted splitting. Concrete pulverizers then allow component-friendly removal of concrete while preserving reinforcement, provided it has been temporarily relieved of load. Rock and concrete splitters are used to create controlled crack lines that overcome compressive forces and divert loads into non-critical paths. Together with hydraulic power packs from Darda GmbH, this creates a finely metered system that makes load redistributions calculable—a key building block for safety, damage minimization, and clean material separation.
Basic principles of the load path in the structural system
Load-bearing structures transfer loads through elements in compression and tension. In reinforced concrete, the compression arch in the concrete and the tensile capacity of the reinforcement often dominate; masonry works predominantly in compression, steel structures combine compression, tension, and bending mechanisms in members and plates. The load path is not a rigid scheme: it adapts to geometry, boundary conditions, and the stiffness distribution. When members are separated or weakened, a load redistribution occurs that produces new support reactions and internal forces. For deconstruction this means: unload before cutting, shore temporarily before removing, and only remove as much load-carrying capacity as is compensated by the support scheme.
Load redistribution during cutting, drilling, and splitting
Every separation cut, every bore, and every splitting operation changes the load distribution. Separation cuts eliminate shear composite action, core intrusions weaken cross-sections, splitting operations create controlled cracks and reduce transverse compression. Used purposefully, these interventions are a tool for unloading control:
- Relief cuts along defined lines reduce restraint forces and prevent unintended crack propagation.
- Rock and concrete splitters create clean fracture patterns through hydraulic spreading forces without significant vibrations—advantageous in sensitive environments.
- Concrete pulverizers remove areas that have been relieved of load step by step, thereby preserving the residual load-bearing capacity of the remaining structure.
- Combination shears and multi cutters are used where composite structures of concrete and steel are present; steel shears perform the cutting of metallic members once they have been relieved or are under controlled suspension.
Tools and methods in the context of load transfer
Deconstruction equipment affects the load path in different mechanical ways. The choice follows the principle: as much force as necessary, as little system intervention as possible.
Concrete pulverizers
Concrete pulverizers crush concrete by forceful gripping and breaking. They are ideal when components have already been shored or locally unloaded. A benefit is the limited input impulse: compared with percussive methods, redistributions remain more controllable, vibrations are reduced, and the load transfer of the remaining structure is less disturbed. This stepwise approach aligns with stepwise removal with concrete crushers where appropriate.
Rock and concrete splitters
Hydraulic splitting technology generates high, locally confined compressive stresses that open the matrix along weak planes. This makes it possible to define intended crack lines that deliberately redirect the load path onto new supports or shoring. Especially in buildings with sensitive equipment or in confined conditions, splitters are a key tool due to low emissions and precise crack guidance.
Hydraulic power packs
Hydraulic power packs provide the necessary energy supply and allow finely graduated control of pressure, flow rate, and cycling. This is crucial for load transfer, because force introduction can be metered in time and magnitude to avoid harmful peak loads.
Combination shears and multi cutters
In composite structures or heavily reinforced concrete, combination shears and multi cutters enable timely separation of concrete and reinforcement. Prior unloading is a prerequisite so that severing tension members does not trigger uncontrolled redistributions.
Steel shears and tank cutters
In steel structures or industrial deconstruction, controlled load transfer often proceeds via suspensions and staged cutting sequences. Steel shears and tank cutters cut beams, plates, and vessels once they are secured by shoring arrangements. The cutting sequence depends on slenderness, cross-section, connection details, and the intended redistribution path.
Areas of application and load-path-oriented procedures
Concrete demolition and specialized deconstruction
At slab edges, drop beams, or shear walls, relief cuts are made first, then crack lines are created with splitters, and finally the sections are removed step by step with concrete pulverizers. Transfer beams and posts temporarily take over the support function until the final geometry is reached.
Strip-out and cutting
Openings in slabs and walls require suspending or shoring the field to be removed before separation cuts eliminate the shear composite action. Concrete pulverizers break elements down into manageable pieces; multi cutters sever reinforcement without compromising tension members in the remaining load-bearing cross-section.
Rock excavation and tunneling
In rock, bedding, joints, and overburden act as natural load paths. Rock splitting cylinders steer stresses so that blocks are detached along existing planes of weakness. Tunnel profiles can be widened in stages without disrupting the stability of the rock mass in an uncontrolled way.
Natural stone extraction
In natural stone extraction, the rock mass is deliberately unloaded to free dimensionally accurate blocks. Splitters generate defined separation planes; load transfer follows the joints toward the quarry floor and working bench. This preserves the quality and shape of the raw blocks.
Special applications
In special situations—such as existing buildings with sensitive use—hydraulic splitting minimizes vibration and noise. Suspensions and redundant shoring secure the load path until shears or pulverizers take over removal. For tanks and steel structures, self-weight is redirected via lifting equipment before cutting.
Planning steps for safe load transfer
- Survey: Record structural system, materials, reinforcement layout, connection details, loads, and boundary conditions.
- Preliminary structural assessment: Evaluate load paths, critical nodes, stability, and possible redistributions.
- Shoring and support concept: Design temporary systems and define tension/compression paths.
- Cutting and splitting sequence: Specify the sequence of cuts, bores, and split points; plan concrete pulverizers for subsequent removal.
- Monitoring: Define measuring points, crack monitors, and control intervals; maintain adjustment reserves.
- Sectional deconstruction: Proceed in small sections, verify results, and adjust parameters (pressure, feed) as needed.
Typical mistakes and countermeasures
- Underestimated secondary loads: Account early for composite shear action and shear redistribution; stagger separation cuts accordingly.
- Eccentric support: Position shoring so that overturning moments are limited and axial forces are introduced centrally.
- Premature cutting of tension members: Cut reinforcement and steel sections only after unloading; use concrete pulverizers to reduce compression zones in a controlled manner.
- Overly large intervention steps: Work in small, manageable sections; combine splitters to initiate cracks and pulverizers for removal.
Measurement and control methods during load redistribution
To verify the load path, use dial gauges on shoring, settlement or deflection measurements, and crack width control. Clear documentation of readings before, during, and after each section increases process safety. The hydraulic controllability of splitters and pulverizers supports reactive fine-tuning if measured values change.
Practical sequence: opening in a reinforced concrete slab
- Clarify the load path; determine slab load direction and reinforcement layout.
- Install suspensions under the field to be removed; set support jacks to defined forces.
- Execute relief cuts at the field edges; pre-drill penetrations.
- Initiate intended crack lines along the opening with rock and concrete splitters.
- Use concrete pulverizers to release the segments and separate materials appropriately; cut reinforcement with multi cutters.
- Check measurements, gradually remove shoring, and finish edges.
Load transfer in steel and composite structures
In steel and composite structures, the load path is often carried by tension/compression members, shear studs, and shear joints. Before cutting with steel shears or tank cutters, members are unloaded via auxiliary beams and suspensions. The cutting follows the rule: secondary members first, then primary members—always only with redundant shoring in place. Concrete pulverizers and combination shears help release composite interfaces without introducing large impact loads.
Sustainability and emissions control in load transfer
A load-path-oriented deconstruction reduces dust, noise, and vibrations by avoiding unnecessary force introduction. Hydraulic splitting and controlled use of concrete pulverizers promote clean separation of concrete and steel and improve recyclability. This not only enhances safety but also optimizes resource use.
Safety and regulatory compliance
For both planning and execution, measures for load transfer must be properly designed, monitored, and documented. Building code requirements and applicable technical rules must be observed. Temporary shoring must be secured against buckling, uplift, and sliding; work and exclusion zones must be clearly delineated. A step-by-step, measurement-supported approach and the finely metered hydraulics of equipment from Darda GmbH help keep load redistributions under control at all times.