Load distribution describes how forces, moments, and deformations in components made of concrete, reinforced concrete, and natural stone are absorbed, undergo load transfer, and are dissipated. Anyone who separates, splits, cuts, or removes material in a controlled manner deliberately reroutes the load paths. This is central to concrete demolition and special demolition, building gutting, rock breakout, and tunnel construction. In practice, tools such as hydraulic wedge splitter, concrete pulverizer, hydraulic demolition shear, or steel shear influence the local stress distribution. Hydraulic power pack determine how evenly forces are introduced. Targeted load distribution reduces damage to the existing structure, prevents uncontrolled crack propagation, and increases safety in the workflow. In such cases, hydraulic rock and concrete splitters enable predictable crack guidance.
Definition: What is meant by load distribution
Load distribution refers to the spatial and temporal distribution of actions (self-weight, live load, earth pressure, prestressing, dynamic excitations) in a structural or rock mass system. These actions are carried via load-carrying members (e.g., compression struts, tension ties in the reinforcement, shear fields) as load paths. In concrete, the microstructure causes redistributions between compression and tension zones; crack formation, friction, and interlock influence the course. In rock, joints, bedding, and grain structure govern the redirection. Interventions such as splitting, cutting, or crushing alter these paths locally and globally. The aim is controlled redistribution so that residual load-bearing capacity and structural stability are preserved.
Fundamentals and mechanisms of load distribution in concrete and rock
In homogeneous, uncracked cross-sections, loads are predominantly distributed through elastic stresses. With increasing demand, crack formation, crushing zones, and redirection of forces into strut-and-tie mechanisms occur. In reinforced concrete, reinforcing bars carry tension and distribute loads through bond and anchorage. Rock masses exhibit anisotropic behavior: joints redirect loads, friction and dilatancy change contact stiffness. Introduced notches, splitting boreholes, or jaw engagement concentrate stresses and promote defined fracture lines. Hydraulic tools modulate load distribution through the way the force is applied (areal, linear, punctual) and through the slope of the force–time curve.
Load distribution in concrete demolition and special demolition
During deconstruction, the sequence of interventions influences load redistribution. Before releasing load-bearing elements, shoring props and temporary bearings must safely take loads. Cutting and splitting sequences control where cracks initiate and how they propagate. Concrete pulverizer act with compressive and shear forces; they create local crushing zones and bring the reinforcement into the force flow. Hydraulic wedge splitter introduce splitting forces via wedges or cylinders and create reproducible fracture surfaces with minimal edge damage. This allows loads to be deliberately released from composite assemblies before they are removed in a controlled manner.
Crack control through splitting forces
Hydraulic wedge splitter cylinders generate high, predominantly static radial pressures. The fracture plane preferentially follows weaknesses such as rows of boreholes. This lowers the risk of uncontrolled crack branching into adjacent components. This controlled crack guidance facilitates the removal of heavy component segments because loads have already been redistributed before the lift.
Shear and compressive zones with the concrete pulverizer
Jaw sets generate concentrated compressive fields and shear lines. The reinforcement bridges cracks, thereby redistributing loads into the bars. A suitable point of attack reduces notch effects and prevents spalling at support edges. In this way, the residual load-bearing capacity of the remaining component is preserved.
Rock breakout, tunnel construction, and natural stone extraction: load redistribution in the mass
In in-situ rock, in-situ and rock mass stresses act. During splitting or tunnel heading, these stresses are released and redistribute. Splitting sequences along existing joints reduce energy demand and promote smooth fracture surfaces. In tunnel cross-sections, load distribution between bench, crown, and invert must be considered to avoid local overloads. Hydraulic wedge splitter and rock wedge splitter allow precise, low vibration levels interventions that change load paths in a predictable manner.
Hydraulic power packs and the dynamics of load transfer
Hydraulic power pack determine force level and rate of force build-up. A gentle pressure ramp reduces impact loads and prevents abrupt redistributions. low-pulsation hydraulic power units improve control, especially for slender components. Pressure holding capability is relevant when cracks are intended to propagate slowly. Matching power pack, hydraulic hose line, and tool minimizes pressure losses and ensures reproducible stress states at the point of intervention.
Planning, calculation, and verification considerations
For interventions in load-bearing structures, load distribution is often estimated using simplified models. Strut-and-tie models represent compression struts and tension ties. Linear-elastic plate approaches and plastic reserves provide bounds for redistributions. In rock, discontinuity models are used that account for joints and contact stiffnesses. The choice of model depends on geometry, material, and intervention. Statements on structural stability must always be made cautiously and based on appropriate assumptions; binding assessments are reserved for the respective project context.
Practical parameters and estimates
- Bearing width and contact pressure: larger contact areas distribute loads and lower crushing/bearing stresses.
- Element thickness and slenderness: thin elements respond sensitively to point loads and notches.
- Reinforcement ratio and anchorage lengths: higher bond reserves favor redistribution into tension ties.
- Rock joint spacing and orientation: align load paths along weak planes.
- Tool force–time history: slower ramp promotes controlled crack formation.
Measuring and monitoring concepts
Simple, robust procedures are helpful for assessing load redistributions. Settlement markers, strain points, crack-width indicators, and dial gauges provide immediate feedback. The tool’s operating pressure can serve as a proxy to interpret material response. Acoustic observation and visual inspections complete the picture. For sensitive structures, continuous measurements with thresholds and coordinated response plans are appropriate.
Influencing factors on load distribution
- Geometry: openings, notches, rows of boreholes, and edges create stress concentrations.
- Material condition: concrete carbonation, chloride contamination, moisture, temperature, and aging cracks change stiffness.
- Connections: joints and bearings with low friction facilitate redirection.
- Reinforcement: position and bond determine the effectiveness of tension ties.
- Site process: sequences, shoring, and transient states govern redistribution.
- Tool selection: splitting (pressure-dominated) versus jaw attack (shear/pressure) versus cutting (separation cut) leads to different stress patterns.
Typical failure patterns and countermeasures
- Point loads at sharp edges: countermeasure via pressure distribution plates, packings, and enlarged bearing areas.
- Uncontrolled crack propagation: countermeasure via rows of boreholes as crack stoppers and staged splitting sequences.
- Spalling at supports: countermeasure via relief cut and gentle force build-up.
- Reinforcement tensile failure: countermeasure by maintaining sufficient anchorage lengths and stepwise separation.
- Damage to the existing structure: countermeasure via low vibration levels methods with hydraulic wedge splitter and adjusted pulverizer setup.
Application examples from practice
- Opening in a reinforced concrete slab: relief via temporary shoring props, then concrete pulverizer for edge removal, followed by hydraulic wedge splitter for the core to guide cracks and reroute loads before lift-out.
- Foundation head separation: pre-drilling and splitting along the row of boreholes so that cutting forces are not introduced into adjacent components; loads migrate into remaining struts and supports.
- Rock removal in tunnel construction: pre-splitting along joints reduces brittle fracture and enables uniform load transfer to the support ring.
- Natural stone extraction: wedge splitters create planar separation surfaces; loads distribute across the remaining bench without impact excitation.
Sequencing and cutting/splitting plans
The order of measures is a key instrument for controlling load paths. A clear sequence minimizes surprises and reduces rework.
- Load-bearing capacity analysis and definition of intermediate states.
- Installation of shoring and pressure distributors, check bearing pressures.
- Preparatory relief cuts at edges and supports.
- Targeted splitting sequences for crack control, starting in areas with low residual load-bearing capacity.
- Removal with concrete pulverizer or hydraulic demolition shear along defined lines; deliberately expose reinforcement.
- Subsequent control of deformations, cracks, and contact pressures.
Tools and load distribution at a glance
Tools influence load transfer in characteristic ways:
- Hydraulic wedge splitter and rock wedge splitter: high, slow pressure introduction; excellent crack control; minimal, low vibration levels at the edges.
- Concrete pulverizer: combined compressive and shear action; good for controlled release of component edges and for exposing reinforcement.
- Hydraulic demolition shear, Multi Cutters, steel shear: efficient separation of steel sections and reinforcement; change tension paths in steel portions.
- Cutting torch: separating interventions in tank shells; load paths in shell structures change locally due to cut-outs.
- Hydraulic power pack: determine the quality of the force–time profile and thus the dynamics of load redistribution.
Checklist for preparing measures with controlled load distribution
- Component and rock survey: geometry, material, joints, reinforcement, rock discontinuities.
- Definition of intermediate states and shoring concepts with sufficient bearing width.
- Selection of tools (e.g., concrete pulverizer or hydraulic wedge splitter) suited to the material and target fracture pattern.
- Definition of splitting and cutting sequences for crack control.
- Plan measuring and observation points; define thresholds and intervention logic.
- Tune hydraulic parameters: pressure build-up, hold times, relief steps.
- Protect edges against notch effects, limit contact pressures.
- Step-by-step execution and documented checks after each intervention.