Concrete Compressive Strength of a Bridge Pier

[Alaani]

I was asked this question in one interview:

What would you do if you find out that the Concrete compressive strength of one pier of a bridge was less than that one in he specifications. Assuming the pier was already poured.

I did not know exactly what is the right answer for this question

 

[concretemasonry]

Were there an test available that were made during construction? As a staring point? It would identify the properties of the concrete delivered, but little regarding the placement methods, curing and any other controls for comparison.

Coring in identical locations could also provide information for a comparison to other piers.

Dick

Engineer and international traveler interested in construction techniques, problems and proper design.

 

[Alaani]

Thanks Mr. Dick!

I believe they were asking me what kind of decision/steps I would take to fix the problem. I assume the concrete strength was already measured and compared and found to be less in strength in that pier. I think it's more like a personality question.

What would you do Mr. Dick if you found yourself in a situation like that ?

 

[dik]

Strength may not be an issue... but durability based on strength or water:cement ratio may be a greater issue. Might be necessary to coat the concrete with a sealer every few years to provide the equivalent resistance.

If cored, then you should establish before hand what the results will mean...

Dik