Commercial Site Visit: Signs of A Poor Concrete Pour

          When pouring concrete it is very important to vibrate the mix as it is poured into the forms to release air pockets and force the concrete to completely settle.  At the bank being constructed close to my home in NJ, I noticed a few areas around the foundation wall were the concrete had not been properly and cracks had already started to develop after only a week.  The first spot was where the brick ledge cut out was near one of the column step downs.

Photo of poorly vibrated concrete.  Lower ledge is a brick ledge for a brick facia to be placed on.

This photo shows a comparison between properly and improperly vibrated concrete.

As you can see the concrete under the baseplate is not level at all.

         This concrete is a large liability because over time there is a good chance this concrete could fail due to freezing and thawing of any water which is able to work its way into this crack.  This crack in the concrete was formed by air bubbles in the concrete mix before it cured.  It is a possibility that this foundation wall could fail inspection because of this crack in the concrete.  This area would be very hard to patch as well because fresh concrete cannon be used to patch this area because it will not adhere properly and the section cannot be replaced because the foundation has to be continuous in order to maintain strength.

          The concrete under the base plate does not need to be perfectly level because the area will be filled with grout after the baseplate's are leveled.