A variety of specialized evaluations and construction activities can be used to identify and remove delaminated areas of concrete. Building Forensics International investigates the delamination of concrete using as many of these activities necessary to locate delaminations in a given concrete surface. One of the common methods is called "Chaining" a broad term of art, like "sounding," which refers to the application of a regular, repeating, percussive force applied to the surface of the concrete for the purpose of generating a series of impacting sounds and audible responses (called "reports") from which a skilled operator can deduce and delimit the presence and extent of slab delamination.
BFI's methods of sounding include the making of careful observations and sketches of condtions which may also independently or in combination suggest delaminations or other noteworthy conditions. BFI conducts these activities in accordance with relevant provisions of ASTM D 4580-03 Standard Practice for Measuring Delaminations in Concrete Bridge Decks by Sounding. Essentially, regularly and uniformly employed impact forces are applied to adjacent surfaces to discern either a variation in the audible report, or a report that is either clear or dull.
The video displays the sounds and technique of testing for delaminations through the use of a hammer. Listen and and see if you can distinquish between the sounds.
BFI Staff Writer