Structural analysis describes the systematic capture, evaluation, and prediction of the behavior of structures, components, and rock formations under load and during interventions. In concrete demolition, special demolition, strip-out, and rock excavation up to tunnel construction, it forms the basis for safe, plannable, and low-emission methods. From structural analysis follow the selection and application of tools such as concrete pulverizers, rock and concrete splitters, combination shears, steel shears, multi cutters, tank cutters, as well as suitable hydraulic power units. It makes load paths visible, reveals weak points and discontinuities, and defines removal sequences—so interventions are targeted, controlled, and within the intended safety framework.
Definition: What is meant by structural analysis
Structural analysis is understood as the holistic investigation of the load-bearing and fabric behavior of concrete, masonry, steel and composite structures, as well as natural rock formations. It encompasses geometry, material parameters (e.g., compressive, tensile, and shear strength), support and connection conditions, crack and joint patterns, reinforcement layouts, corrosion states, and existing or expected loads. The goal is to predict the residual load-bearing capacity and the effects of planned interventions, minimize risks, and define the technical approach—such as separation cuts, splitting lines, jaw engagements, or cutting sequences. In practice, structural analysis provides the decision basis as to whether, for example, concrete pulverizers or rock and concrete splitters represent the more suitable method and how hydraulic power packs are sized.
Methodology of structural analysis in deconstruction and rock excavation
The methodology follows a structured sequence: review of documents (drawings, structural design, construction stages), site walk and condition survey, metrological verification, derivation of a load and stability model, definition of intervention and safety measures, monitoring. In concrete and reinforced concrete components, reinforcement layouts, supports, bonds, and crack patterns are recorded; in rock masses, discontinuities, joint systems, stratification, degree of weathering, and water flow are the focus. This yields a practice-oriented action model that defines the order of interventions, the selection of tools, and the hydraulic parameters. A good structural analysis is iterative: observations during the intervention feed back into the assessment so that the approach can be adapted as required.
Understanding the load-bearing system: load paths, supports, and weaknesses
Structures behave only as safely as the knowledge of their load paths. Those who read load-bearing action, support conditions, and weaknesses precisely reduce unforeseen load redistributions during deconstruction.
Load transfer in reinforced concrete
Reinforced concrete members combine concrete compression zones and reinforcement tension zones. Interventions must place separation interfaces so that tensile forces are released in a controlled manner. Concrete pulverizers are suitable where concrete is purposefully crushed and the reinforcement exposed and then cut with steel shears or multi cutters. Splitting methods are appropriate when compression-dominated members are to be separated along defined splitting boreholes without additional crack propagation.
Masonry and composite members
Masonry exhibits anisotropic properties along bed joints. Here, low-vibration splitting methods prove effective to avoid shaking the structure. Local cuts with combination shears or notching of secondary components facilitate controlled removal steps.
Rock mass and tunnel advance
In rock, joint orientation, crack spacing, roughness, and water influence removal behavior. Rock and concrete splitters together with rock splitting cylinders act purposefully along prepared boreholes. Structural analysis defines drilling patterns, wedge angles, and the optimal triggering sequence to secure the stability of adjacent areas.
Determining material and fabric parameters
For robust planning, parameters are determined as non-destructively as possible and checked for plausibility.
Concrete and reinforcement
- Surface visual inspection: crack types (shrinkage, settlement, structural cracks), spalling, corrosion indicators.
- Rebound testing to estimate compressive strength in combination with core findings, where permitted.
- Ultrasonic transit-time measurements to assess homogeneity and detect defects.
- Reinforcement location and cover using electromagnetic methods; derivation of bar diameters and spacings.
- Moisture content, chloride contamination, and carbonation as influencing factors on residual load-bearing capacity.
Rock and natural stone
- Discontinuity analysis: joint families, dip/strike, spacings, roughness, infillings.
- Quality parameters of the rock mass (e.g., RQD) as a measure of blockiness.
- Influence of water: pore and joint water, uplift, erosion marks.
- Schmidt hammer hardness or rebound values for an initial classification of compressive strength.
Tool selection based on structural analysis
The choice between concrete pulverizers and rock and concrete splitters is based on material, geometry, surroundings, and target operation. In addition, combination shears, multi cutters, steel shears, or tank cutters are used when reinforcement, sections, or vessels must be cut. Structural analysis provides the decision criteria:
- Concrete pulverizers: suitable for well-accessible components when concrete is purposefully crushed and reinforcement subsequently cut; advantageous for members with high reinforcement density when visual control is required.
- Rock and concrete splitters: suitable for massive, compression-bearing elements or rock when a defined separation plane along boreholes is to be created; low-noise and low-vibration, good for sensitive environments.
- Combination shears and multi cutters: universal for masonry, concrete edge areas, sheet metal, and composite members in strip-out and when cutting attachments.
- Steel shears: for rolled steel sections, beams, reinforcement bundles, manhole covers, and metallic connections.
- Tank cutters: for tanks, pipelines, and hollow bodies where a defined cutting path is required.
Hydraulic power packs: pressure, flow rate, and supply logic
Hydraulic power packs provide the required system pressure and flow rate for pulverizers, splitting cylinders, and shears. Structural analysis results in performance requirements: member dimensions, strengths, and desired cycle times determine force and speed demand. It is important to coordinate power pack performance, hose lengths, and valve technology so that the planned force is available at the tool tip.
Estimating required force
For splitting methods, the required splitting force is derived from borehole diameter, wedge geometry, material tensile strength, and desired split length. For pulverizers, the lever ratio, jaw opening, and the material properties of the concrete determine the necessary crushing force. Conservative sizing with safety reserves is common; fine-tuning is carried out through trials at test spots.
Cutting and splitting planning: sequence, stability, emissions
The removal sequence avoids undesirable load redistributions and minimizes noise, dust, and vibrations. Structural analysis defines cutting depths, stages, lifting points, and safety measures.
Removal sequence and residual load-bearing capacity
- Preparatory relief: removal of non-load-bearing attachments, strip-out, exposure of reinforcement nodes.
- Defined separation planes: drilling patterns and splitting lines or pre-separation cuts for controlled intended fracture surfaces.
- Controlled main removal: use of concrete pulverizers or rock and concrete splitters according to the sequence plan.
- Touch-up and reinforcement cutting: deploy steel shears or multi cutters, secure remaining pieces.
- Section-by-section monitoring: observe and document deformations, crack progression, and vibrations.
Measurement and testing methods in practice
A methodical mix increases the significance. Visual inspection, simple impact and rebound tests, ultrasonics, reinforcement detection, endoscopy in boreholes, and geodetic measurements complement one another. In rock, compass measurements on joint surfaces, simple shear tests on hand specimens, and moisture monitoring are useful. All results are checked for plausibility and compared with experience from similar construction methods.
Documentation, monitoring, and quality assurance
Traceable documentation is part of structural analysis. Logs, photos, sketches, measurements, and changes to the approach are recorded continuously. For critical sections, monitoring with thresholds for deformations, vibrations, and noise is recommended. This allows interventions to be controlled with low emissions and adjusted immediately if necessary.
Fields of application: overview of structural analysis
In concrete demolition and special demolition, structural analysis creates clarity about removal paths, temporary stabilization, and tool deployment. Strip-out and cutting benefit from targeted separation of secondary members and reinforcement. In rock excavation and tunnel construction, it defines drilling patterns, splitting sequences, and safety measures. In natural stone extraction, analyzing joint systems leads to clean, dimensionally accurate blocks. For special operations with complex geometries or sensitive environments, structural analysis ensures a low-emission, controlled approach. In all the areas mentioned, concrete pulverizers and rock and concrete splitters are key tools whose use is methodically prepared by the analysis; supplemented by hydraulic power packs, combination shears, multi cutters, steel shears, and tank cutters.
Risk assessment and legal aspects
Structural analyses serve risk minimization. They form the basis for protective measures, workflows, and the selection of suitable equipment. Legal frameworks, standards, and regulatory requirements must be observed depending on the project and region. Statements here are general and do not replace a case-by-case review. As a rule: plan safety reserves, define responsibilities clearly, document changes, and obtain approvals.
Typical mistakes and how structural analysis avoids them
- Incomplete survey of existing conditions: leads to unexpected reinforcement layouts or voids. Countermeasure: systematic detection and trial exposures.
- Underestimated residual load-bearing capacity: causes uncontrolled cracking. Countermeasure: conservative design, step-by-step approach.
- Wrong tool selection: increases emissions or prolongs cycle times. Countermeasure: decision matrix based on material, access, objective, environment.
- Unclear removal sequence: promotes load redistributions. Countermeasure: defined sequences, auxiliary shoring, monitoring.
- Insufficient hydraulic coordination: inadequate tool performance. Countermeasure: design pressure and flow rate for the intended use, check lines.
Core concepts for everyday work
What is essential is thinking in load paths, separation planes, and stages. Concrete pulverizers offer visual control during the intervention and are ideal for exposing reinforcement and crushing members with positive engagement. Rock and concrete splitters create defined separations along boreholes and protect the surroundings through low vibrations. Combination shears, multi cutters, steel shears, and tank cutters complement the process with precise cutting operations on metal and composite members. Hydraulic power packs provide the energy; their correct sizing is an integral part of structural analysis.
Checklist for work preparation
- Review documents: drawings, structural calculations, construction stages, material specifications.
- Site walk and findings: crack patterns, supports, connections, voids, moisture.
- Measurements: strength estimates, reinforcement detection, ultrasonics, joint analysis.
- Load model: load paths, residual load-bearing capacity, temporary stabilizations.
- Tool selection: concrete pulverizers or rock and concrete splitters, supplemented by combination shears, multi cutters, steel shears, tank cutters.
- Hydraulic planning: pressure, flow rate, hose routing, cycle times.
- Sequence plan: separation cuts/drilling patterns, removal sequence, lifting points.
- Protective measures: barriers, dust and noise reduction, monitoring.
- Documentation: target/actual comparison, approvals, adjustment rules.