Post concrete inspection of concrete structures is essential to check for any damage or defects that may require repair. Immediately after stripping the formwork, all concrete members casted are carefully inspected and any defective work or small defects either removed or made good before the concrete has thoroughly hardened. Post concrete inspection involves both eye inspection and testing of concrete to achieve its goals.
The post concrete inspection of buildings may be conducted by site engineer or foreman. The report produced would serve as a guide for site engineer to repair defects prior to full acceptance of the structure.
Post Concrete Inspection and Testing of Concrete Buildings
- Record time of shutter stripping and check for compliance with the specifications
- Record and verify curing method
- Verify date and time of commencement of curing
- Inspect curing process daily and randomly and record any non-compliance such as surface is not kept wet, membrane surface damaged. Corrective actions taken for each day.
- Check concrete surface to specify defects such as surface honeycombing, voids, and ridges. Commonly, repair of these defects shall be requested as soon as possible and weak areas shall be removed to reach sound concrete.
- Upon shutter stripping, concrete shall be inspected for spalling and cracks. These deficiencies need to be examined to find out whether they are structural or not.
- It is necessary to check dimensions of elements to make sure whether any displacement occurred during concrete pouring or not. This can be accomplished with the help of surveyor.
- Structural elements shall be examined to specify whether they have exceeded tolerances in terms of dimensions and positions.
- If 7 days concrete strength test result demonstrate that the designated concrete strength at 28 days of age may not be achieved, site engineer needs to report the condition of the structure immediately to the project manager to take necessary actions.
- In case of doubt regarding the grade of concrete used either due to poor workmanship or based on results of cube strength tests, the compressive strength test of concrete on the basis of core test, ultrasonic test and/ or load test is carried out.
- When results of cube strength are observed to be lower than the required designed strength at 28 days as per specifications, ultrasonic test is carried out by the digital ultrasonic concrete tester.
- If the ultrasonic test does not satisfy the requirement of the designed structure, concrete can be rejected or remedial measures are considered to make the concrete suitable for given structure.
- In case cube tests give unsatisfactory results, the conclusive tests such as ultrasonic pulse test or core test is carried out to prove the suitability of concrete.
- If the results of any test prove unsatisfactory or the structure shows signs of weakness, undue deflection or faulty construction, the concrete members should be repaired or rebuilt.
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