We have extensive experience in inspections and condition assessments of various concrete structures. We investigate, among other things, damage caused by reinforcement corrosion, frost, fire, moisture and alkali silica reactions (ASR). We help you with the whole or parts of an investigation. This is how we work:
The condition assessment can be divided into three levels:
- Level 1 – Simple state analysis
- Level 2 – Extended state analysis
- Level 3 – Comprehensive state analysis
Level 1 – Simple state analysis
Here, an assessment of the condition is made based on visual observations, possibly in conjunction with measuring the cover layer and recording the depth of carbonation. Usually the survey is done without scaffolding. The main tools for this analysis are photography/filming and a general registration of cracks, cover layer condition, settlements, displacements, rust precipitations, etc. Comparisons with previous analyses are made and plans for higher level analysis are made. Can also evaluate the need for preventive measures.
Level 2 – Extended state analysis
An extended condition assessment includes a visual examination of the entire structure. Usually with the help of scaffolding or a lift. Here it is important to find the cause of the damage, map the extent of the damage and investigate whether the extent of the damage is expected to increase. A Level-2 survey normally includes measurement of carbonation depth, cover layer measurement, chloride content, measurement of crack widths, registration of boom, adhesion to concrete, exposure of parts of the reinforcement. In some cases also potential measurement, measurement of reinforcement continuity, possibly measurements of deformations and settlements. The information is used to compile a basis for design and also for maintenance planning.
Level 3 – Comprehensive state analysis
In addition, a more in-depth investigation of the degradation mechanisms identified in Level 2 and strength testing. Usually, a calculation check is also carried out here for parts of or the entire structure based on the condition analyses carried out. In some cases, measuring equipment can be installed on the structure to monitor changes over time, which in turn provides additional information for the condition analysis. In addition, various methods of non-destructive testing are often used to map the condition of the structure.
Inspection and condition assessment – survey
The table below summarizes the different levels of state analysis in general depending on the parameter to be investigated.
| Parameter to investigate / Level of analysis | 1 | 2 | 3 |
|---|---|---|---|
| Visual examination | ✓ | ✓ | ✓ |
| Covering layer | ✓ | ✓ | ✓ |
| Carbonation depth | ✓ | ✓ | ✓ |
| Chloride content | (✓) | ✓ | ✓ |
| Potential measurement (EKP) | ✓ | ✓ | |
| Exposure of reinforcement | ✓ | ✓ | |
| Measurement of cracks and crack depth | ✓ | ✓ | |
| Boom control | (✓) | ✓ | ✓ |
| Adhesion | ✓ | ✓ | |
| Electrical resistance | ((✓)) | ((✓)) | |
| Checking the tensioning reinforcement | ((✓)) | ((✓)) | |
| Compressive and tensile strength | ((✓)) | ||
| Fiber content (Only for fiber reinforced constructions) | ((✓)) | ||
| Ultrasound | ((✓)) | ||
| Permeability measurement | ((✓)) | ||
| Corrosion rate | ((✓)) | ||
| Relative humidity | ✓ | ||
| temperature | ((✓)) | ||
| Dimensional control – geometry | ✓ | ||
| Test load, part or whole structure | ((✓)) | ||
| Reinforcement control | ✓ | ✓ | |
| Settlements, deformations | ((✓)) | ✓ |
The strategy can then be:
- Do nothing over certain time, but monitor
- Analyze carrying capacity further
- Prevent or mitigate further degradation
- Reinforce or repair and protect all or part of the structure
- Demolish all or part of the structure
The most appropriate strategy and action will need to be discussed with the owner and future needs.
Sampling
We also take samples in the form of drill cores to check the strength of the concrete and for thin section analysis where you can examine frost damage, leaching, delamination, ASR attacks, cracks, water cement numbers, chemical attacks and sulfate attacks. The samples are taken from a drill core or a piece of concrete. In addition, we can carry out chloride and carbonation analyses of a specific concrete structure.