None of the tested configurations included a concrete slab; thus, the slab must be isolated from the column to avoid developing unintended and unproven mechanism in the connection as built during a seismic event. Further, no shear studs were present in the tested configuration; therefore, as a result, shear studs are precluded in the as-built connections in a conservative but consistent decision aimed at preventing potential fractures from initiating at the stud welds in regions expected to undergo significant inelastic strains. Given that the distance from the face of the column to one beam depth beyond the shear bolts farthest from the column may be a large distance, the requirement that studs be omitted in this region may create difficulties for composite beam systems. However, the requirement is felt necessary to preserve the anticipated performance of the connection. It is speculated that the presence of the bolts and nuts connecting the beam flange to the T-stem (the shear bolts) will transfer some shear between the steel and concrete without compromising the seismic performance of the connection.
Double-tee connections tested at Georgia Tech ranged in stiffness from connections that were clearly fully restrained (FR) to nearly partially restrained (PR). The AISC Seismic Provisions explicitly permit PR connections in OMFs but are silent on the use of PR connections in IMFs and SMFs. This standard precludes the use of PR double-tee connections until the issue can be considered in more detail. Step 13 of the double-tee design procedure includes a check of the connection stiffness to ensure that it satisfies the FR criteria.