Structural diagnostics and service life design

Innovative know-how in the fields of  structural diagnostics and  service life design

The durability of reinforced concrete structures can be impaired by environmental influences. In this connection we can offer you help with the diagnosis of existing structures, assessment of the inspection results and the planning of any repair work required.

Our experienced interdisciplinary team of engineers, chemists, mineralogists, geologists and physicists will also gladly advise on the clarification of damage issues, such as crack formation or surface discoloration on structures and elements made of mortar and concrete.

We offer the following services in the fields of structural diagnostics and service life design:

Structural diagnostics

The objective of the structural inspection is to obtain information on the overall condition of the structure. In the process, we identify possible damage mechanisms and then together with you we plan the further course of action required to maintain and repair the structure.

We are pleased to provide assistance in the following areas:

  • Recording of damaged and non-damaged parts of concrete constructions
  • Identification and assessment of damage mechanisms, e.g. crack formation and loss of strength
  • Damage prediction, e.g. ASR residual expansion potential
  • Clarification of the causes of efflorescence and discoloration
  • Estimation of the residual service life of the structure
  • Determination of the repair work required for the structure

Following structural diagnosis, we also perform BIM-based repair planning for you if required (see below). Benefit from this integrated approach and our sound expertise.

Selected services in the field of structural diagnostics

ServiceMethod

Taking of samples from the structure, e.g. drill cores for testing compressive strength

DIN EN 12504-1
Drill dust sampling, e.g. to determine the chloride content of concreteGerman Committee for Structural Concrete (DAfStb),
Handbook 401
Non-destructive testing of compressive strength (rebound number)DIN EN 12504-2
Crack recording, use of gypsum marks
Analysis of the composition of hardened concrete
Non-destructive determination of concrete coverelectromagnetic
Leaching tests (tank test/shaking test)CEN/TS 16637-2/
DIN EN 12457
Determination of asbestos VDZ
Qualitative and quantitative x-ray phase analysisVDZ
Structural analysis of thin sections by means of light microscopyVDZ
Structural analysis by means of scanning electron microscopyVDZ
Thermal phase analysisVDZ
Surface tensile strength, pull-off strength, tensile adhesion strength
Water absorption at atmospheric pressure/at 15 MPaGerman Committee for Structural Concrete (DAfStb), Handbook 422 DIN EN 480-5
Capillary water absorptionGerman Committee for Structural Concrete (DAfStb),
Handbook 422 DIN EN 480-5
Pore content and pore distribution in concrete, mortar and hardened cement paste using mercury intrusion porosimetry
Permeability measurementGerman Committee for Structural Concrete (DAfStb),
Handbook 422
60°C concrete test or 40°C fog chamber on drill cores (with or without alkali supply): Determination of residual expansion potential due to ASRVDZ
Post-cracking flexural strength on steel fibre concrete beams, e.g. taken from an industrial concrete floorBased on German Comittee for Structural Concrete (DAfStb) Guideline
Determination of content and orientation of steel fibres (CT)Computer tomography
(on sub-contract basis)
Ultrasonic time-of-flight non-destructive test methodVDZ

Service life design

Service life design

The probability of the occurrence of reinforcement corrosion arising from the carbonation of the concrete cover or the penetration of chlorides into the concrete can be estimated by way of probabilistic serviceability limit state studies. The conclusions drawn from this with regard to the durability of reinforced concrete elements can provide you with a basis for planning new construction work and remedial measures.

We would be pleased to assist you with the following activities:

  • Serviceability limit state studies for reinforced concrete elements
  • Serviceability limit state studies for repair measures (concrete substitution)
  • Estimation of the residual service life of existing reinforced concrete elements
  • Performance-related  concrete  design  for  specified  service life or durability requirements


Typical applications include:

  • Usage of new materials (concretes, concrete substitution systems), the durability of which has to be ensured prior to use in the structure
  • Analysis of the consequences of irregularities or shortcomings during the construction phase for the reliability of the structure
  • Design of elements subject to exceptional requirements in terms of durability
  • Verification of a sufficiently low risk of corrosion for structures with a particularly long service life (> 50 years)
  • Determination of layer thicknesses for concrete substitution in maintenance planning
  • Assessment of the effects of changes to exposure (e.g. due to different usage or different environmental impact) as a basis for the production of maintenance concepts

The digital twin of existing structures

The digital twin of existing structures

We can generate the digital twin of your existing structures. This will provide you with a powerful and innovative tool for the management and maintenance of your existing structures. The 3D model enables operators of structures to efficiently analyse all the structural data collected.

The more complex and challenging the geometry of a structure, the more valuable is the BIM method as a planning tool for building owners and designers. Section views can be easily created through the models. Conflicts between jobs on site (including repair work) can be clearly identified in the 3D model.

As an additional benefit, the results of the structural diagnostics can be stored as information in the 3D models. This also applies to the results of service life design (see above) and the updated versions of this resulting from regular inspection of the structure.

Structures can be modelled to differing degrees of detail, from

  • LOD100 (rough planning) to
  • LOD300 (detailed planning) and
  • LOD500 (model of existing structure).

Once we have created the digital twin of your existing structures, the 3D models can also be used for BIM-based repair planning.

BIM-based repair planning

BIM-based repair planning

For the purposes of repair planning, we can present your structure as a 3D model or BIM file. This involves modelling the structure in a virtual space based on existing plans and the results of structural examinations. Modelling of the structure using a digital point cloud is another possibility.

The results of the structure examination, e.g. test locations, drill core sampling locations, chloride profiles and the results of the reinforcement scanner, can be incorporated into the BIM model. The actual state is recorded in digital form. This permits planned/actual state comparison. The material properties established during the structure examination are stored in the 3D model as element-specific information. Repair planning is also performed on the 3D model. You will receive the structure model in the form of an IFC file.

Thus we provide you with two services at the same time:

  • Creating the digital twin of the existing structure
  • Repair planning and repair of the structure with the aid of a 3D model


Further advantages of the model-based approach include:

  • Contractors can use the 3D model as a basis for calculating quantities.
  • BIM-based planning and execution reveal conflicts between trades at an early stage.
  • The entire planning and construction process is highly transparent.
  • Building work is still performed on the basis of drawings, but these are derived from the model.
  • On the construction site, the 3D model is a source of additional information and a basis for discussion.

Contact

Dr. Stefan Kubens

Dr. Stefan Kubens

Phone:
+49-211-45 78-343

Fax:
+49-211-45 78-219

Contact

Dr. Wibke Hermerschmidt

Dr. Wibke Hermerschmidt

Phone:
+49-211-45 78-374

Fax:
+49-211-45 78-219

Service Offer

VDZ services in the fields of structural diagnostics and service life design

Overview of services in the fields of structural diagnostics and service life design