Din 1045

DIN 1045 defines the technical rules for structures made of concrete, reinforced concrete, and prestressed concrete. It shapes the planning, design, execution, and testing of concrete components—and thus also their safe maintenance, selective deconstruction, and concrete demolition. For work preparation in deconstruction, for example when using concrete demolition shear or rock and concrete splitters from Darda GmbH, the standard provides the basic data: concrete compressive strength class, cover, exposure classes, reinforcement guidance, and tolerances. Because a large number of structures in Germany were built according to DIN 1045, understanding the standard is crucial for all areas of application—from concrete demolition and special demolition through building gutting and concrete cutting to special operations.

Definition: What is meant by DIN 1045

DIN 1045 (structures made of concrete, reinforced concrete, and prestressed concrete) is a set of standards that specifies the fundamental requirements for the design, detailing, execution, and testing of concrete structures. It regulates, among other things, material parameters, verification formats, concrete cover, durability, and execution qualities. In practice, various parts of the standard are encountered: design and detailing (DIN 1045‑1), concrete properties and conformity to complement European rules (DIN 1045‑2), testing (DIN 1045‑3), as well as execution (DIN 1045‑4). Although Eurocode 2 with national annexes is decisive today, DIN 1045 remains relevant for the existing building stock, for the assessment of existing structures, and for planning deconstruction measures.

Structure and scope of the standard

The standard covers the essential sections of concrete construction from planning to execution and testing. For deconstruction it is important which edition or version was applied to the structure, because key component parameters can be derived from it.

Key regulatory contents

• Design and detailing: safety concept, verification of ultimate and serviceability limit states, minimum reinforcement, crack width limitation.
• Durability: exposure classes (e.g., XC, XD, XS), concrete cover, minimum cement contents, water–cement ratio.
• Concrete and reinforcement: concrete compressive strength class (e.g., C20/25 to C50/60), properties of reinforcing and prestressing steels.
• Execution: tolerances, joint rules, compaction, curing, manufacturing and testing specifications.
• Testing: parameters from fresh and hardened concrete tests, conformity, and surveillance.

Significance of DIN 1045 for concrete demolition and special demolition

Deconstruction planning benefits from standard-based component data. Concrete cover, reinforcement ratios, member dimensions, joint locations, and strength classes guide the selection of suitable separation and splitting methods. In massive members with high compressive strength, rock and concrete splitters can purposefully exploit the low tensile strength of concrete. In reinforced elements, concrete demolition shear support controlled removal, while bars and meshes are cut with steel shear. DIN 1045 provides the expected concrete and reinforcement properties that are essential for a safe, low vibration levels, and plannable sequence—whether in concrete demolition and special demolition, in building gutting and concrete cutting, or in special operations with restricted boundary conditions.

Material parameters and exposure classes according to DIN 1045

Knowledge of the material classes used according to DIN 1045 facilitates the prediction of cutting and splitting behavior. Typical concrete compressive strength class ranges from C20/25 to C50/60; higher classes are found in load-bearing cores, columns, or bridge elements. Exposure classes (e.g., XC3, XD1, XS2) influence concrete cover and durability—both affect access to reinforcement. Larger concrete covers lengthen the path to the steel and alter the initial crack patterns during hydraulic splitting.

Effects on process engineering

• Splitting technique: High compressive strength increases the required splitting forces, but low tensile strength remains exploitable; borehole spacings and diameters must be designed accordingly.
• Shear technique: With dense reinforcement and higher ductility of the member, stable, controlled crushing and shearing processes are advantageous.
• Steel separations: Exposure-driven larger concrete cover delays exposure; for reinforcing steels, steel shear are used, and for embedded parts, multi cutters may be considered.

Concrete cover, reinforcement, and their influence on separation and splitting techniques

DIN 1045 defines minimum concrete covers depending on exposure and member category. This is crucial for the work sequence: only after the cover is overcome can the reinforcement be cut or released. For massive walls and foundations, rock and concrete splitters are suitable to break the cover in a controlled way and predefine crack zones. Afterwards, concrete demolition shear enable segmental removal, with exposed steels cut by steel shear. In slab areas with reduced cover, a shear- or saw-first sequence may be preferred.

Joints, predetermined breaking points, and tolerances

Joint patterns and execution tolerances according to DIN 1045 help plan cutting and splitting lines. Construction and expansion joints, anchor and bearing zones, as well as minimum structural reinforcement provide potential starting points for selective deconstruction with reduced vibration and lower noise.

Planning and sequence in existing structures: From record assessment to method

For the deconstruction of structures built to DIN 1045, a coordinated approach has proven effective. The steps are not exhaustive and must be adapted to the project.

1. Existing-structure analysis: drawings, samples, site visits; estimation of concrete compressive strength class, cover, reinforcement ratio, and member thicknesses.
2. Method selection: matching component parameters with suitable methods (splitting, shearing, cutting, sawing); considering vibration, noise, dust exposure, and accessibility.
3. Sequencing: defining the order—e.g., pre-drilling, hydraulic splitting, shear removal, steel separation.
4. Hydraulics and power supply: sizing the hydraulic power units with regard to expected forces, cycle times, and duration of use.
5. Component-wise disposal: separation of concrete, reinforcing steel, and embedded parts to promote recycling (e.g., recycled concrete share).
6. Verification: documentation of measures and control of target values (e.g., vibration, dust exposure, cut dimensions).

Tools and methods in the context of the standard

The standard provides the technical cornerstones from which an appropriate tool selection is derived—always related to the specific application.

• Rock and concrete splitters: for massive, heavily reinforced members and foundations; exploit the low tensile strength of concrete, reduce vibration, and are suitable in sensitive areas.
• Concrete demolition shear: for controlled removal of reinforced concrete, exposing and cutting reinforcement in a step-by-step process.
• Rock wedge splitter: for rock excavation and tunneling as well as natural stone extraction; in tunneling, often following work on inner concrete linings.
• Combination shears and multi cutters: for mixed materials, embedded parts, and ductile steel components in the concrete composite; includes hydraulic shear where appropriate.
• Steel shear: for load-safe cutting of exposed reinforcement, sections, and embedded parts.
• Tank cutters: for adjacent steel vessels, pipelines, and apparatus connected to concrete structures.
• Hydraulic power pack: torque- and force-stable supply of hydraulic tools; sizing according to member thickness and required cycle time.

Specific structure generations and older editions

Older structures were designed and executed according to previous editions of DIN 1045. Concrete covers, strength classes, and detailing rules may differ. Joint arrangements, minimum reinforcement, or tolerances often vary. Therefore, a member-specific condition survey is required for planning splitting patterns and shear grips. In case of doubt, material samples and low-damage tests should support the assumptions.

Normative interfaces: Eurocode 2 and DIN EN 206

Today, Eurocode 2 with national regulations is the governing basis, interacting with DIN EN 206 (concrete) and associated national provisions. For existing structures, the logic of DIN 1045 remains central: exposure classes, concrete cover, minimum reinforcement, and verification formats. In deconstruction, the interface between these sets of rules is especially relevant for material parameters and durability assumptions.

Safety, health, and environment in deconstruction

The component properties expected under DIN 1045 also influence protective measures: with dense reinforcement, the number of steel separations increases; for massive members, a low-vibration approach is sensible. Hydraulic methods—splitting, shearing, and cutting—enable an approach aligned with occupational safety, reducing noise, vibration, and dust exposure. Measures for water management and dust suppression must be planned early. Statements on permits, limits, or obligations must always be checked project-specifically, as they depend on local requirements.

Practical examples by component type

Massive foundations and machine blocks

Often high strength classes and large concrete cover. Procedure: pre-drilling, hydraulic splitting with rock and concrete splitters, segmental removal; cut exposed reinforcement with steel shear. For machine foundation, adapt forces and sequences accordingly.

Reinforced concrete walls and shafts

Defined shear grips are possible due to reinforcement layout. Joints and anchor zones facilitate sequence planning. In sensitive areas, concrete demolition shear offer a controlled alternative to percussive methods.

Slabs and plates

Lower concrete cover and regular reinforcement grids favor shear and cutting sequences. Cut edges and openings are planned along the reinforcement logic.

Bridge curbs and edge beams

Exposure leads to higher concrete cover and corrosion-relevant details. Controlled removal with shears, supplemented by steel separations, protects adjacent components.

Documentation and quality assurance

Documentation is oriented to the parameters of DIN 1045: strength assumptions, exposure classes, concrete cover, and tolerances. In deconstruction it is supplemented by evidence of vibration and dust reduction, material separation, and dimensional accuracy of cuts and splitting lines. This results in a robust protocol that supports the safe and traceable implementation of the measure.