The minimum diaphragm thickness is controlled and reported automatically according to Table 8.3.1.1 for flat slabs.

The minimum diaphragm thickness is controlled and reported automatically according to Table 8.3.1.2 for beam-to-slabs.


Symbols

h = overall thickness, height, or depth of member, in.
ln = length of clear span measured face-to-face of supports, in.
fy = specified yield strength for nonprestressed reinforcement, psi
αfm = average value of αf for all beams on edges of a panel


Minimum diaphragm thickness

There are two different slab thickness limits according to flat slab and beam-to-slab. According to 12.3.1.2, floor and roof diaphragms are controlled automatically in accordane with their slab type.

Detailed information: One-Way Slab Design Limits and Two-Way Slab Design Limits.