Expert: Dr. Abdulaziz Jarkas - 3/5/2007

Question
Dear Sir,
I'm working at a Construction Project site. Recently we have faced a problem of "Honey-Combing" in one of our structures of Overhead Water Tank (already constructed). Percentage affected area may be taken as 2.5 % total (three different patches of 2 sft. of area each, within a total area of 400-500 sft.). In order to amend it, we have an option of dismantling. But we don't want to go for that. If you can suggest for any other possible solutions with reference to International Safety Standards.Any reference regarding "Safety limit" or thumb rule which confirms us the minimum criteria of honey-combing in a structure that assures our structure to be at safer side at this stage? Your immediate response shall be highly appreaciated.
Regards,
Anika
Architectural Engineer
Forman Christian College Site

Answer
Dear Anika,

Your problem is indeed a simple one!

Just expose the affected area and refill with epoxy based material having a higher compressive strength of the existing concrete.

As for the safety limit, I'm not sure that such a criterion does exist! It is not unusual for the concrete to honey comb, and we usually just treat the affected areas! I have witnessed stripping off almost the whole soffit of an 18 ft major beam due to the same problem on one of the Construction sites.

Hope this helps!

Dr. A. Jarkas