Deep Slabs Subjected to Static and Blast Loading

The results of experimental static tests on square, deep, reinforced and plain concrete slabs show that the governing mode of failure is shear. The magnitude of static failure overpressures ranged from 810 psi to 1,683 psi. The deep, reinforced and plain concrete slabs tested in the field were subjected to a peak air-blast pressure of approximately 5,000 psi. Based on post test visual examination of the field test slabs, their response appeared to be similar to the shallower deep slabs tested statically, i.e. the mode of response was shear. Static tests were conducted on 21 deep-slab specimens having a constant span-to-thickness ratio, L/t, of 4.12. Six additional deep-slab specimens were included in a field test, with three slabs having an L/t ratio of 3.5 and three a ratio of 2.6. All of the slabs had a constant square length of 30.25 in. and were supported over a 24-in. diam clear span.