Multiple Anchors Work As Group for Side
Blowout Check Along Width Edge

ACI 318-11 D.5.4.2

When s22 <= 6c , edge anchors work as a group.
Nsbg = [1+ s /(6c) ] x Nsb

where    s = s2    s22= s2 / (nbw-1)   
             c = min(c1 , c3)


ACI 318-11 D.5.4.2