(WPC), took exception to the prohibition against pneumatically applied concrete
. It argued that shotcrete was more reliable and structurally equal to cast-in-place concrete and resisted cracking the same as any other method.
"Certain floors had to have pneumatically applied concrete
, shotcrete applied to the underneath side of the floor to strengthen [the floors] to bring them up to the right seismic design," he says.
Acceptable options include trowel-applied specialty concretes or mortars, pneumatically applied concrete
(shot-crete), cast-in-place concrete, and pre-placed aggregate concretes.