Condition Assessment and Distress-diagnostic Techniques

This paper discusses the critical requirement of the correct condition assessment of concrete structures and an open minded approach to assess the cause of structural distresses and related symptoms. What is visible to one is only the symptom. This will enable identification of the problem in the first place. This in turn will lead to the correct solution to the distress of the structure. The diagnosis has to be based on what is visible and duly correlated to the test reports and what one perceives. There are many possible causes that can cause a particular symptom and one has to be methodical and logical in one’s approach to narrow down the possibilities to arrive at the right cause. This paper also shows some of the interesting assessments that the author has made which do not fall under the usual ones.

N S Moorthy, DicoTech LLC, Concrete Repairs and Engineering, UAE

Condition Assessment

What is condition assessment? It is systematic and logical examination of a structure to identify the cause of the distress. The examination would cover visual inspection, checking of documents; such as drawings, construction records, previous investigation reports (if any), determination of the time of appearance of the defect and analyzing the test reports. Many times one would come across that many of these may not be available! But still one has to find ways and means of overcoming this.

Nature of Distresses

Various kinds of distresses that we come across normally largely cover cracks Fig 1.


And the cracks could be due to many reasons. Shrinkage cracks, plastic shrinkage cracks, plastic settlement cracks, early heat of hydration cracks, long-term thermal shrinkage cracks, excess stresses in flexure, tensile, shear, punching etc. are the nature of cracks to name a few. It could also be due to corrosion of reinforcement or unequal foundation settlement.

Besides cracks, there are other symptoms of leakages, seepages, discoloration and pigmentation of concrete. i.e. stains on concrete could also lead to important conclusions.