Title:
Design Method for Imposed Rotations of Interior Slab-Column Connections
Author(s):
Carl Erik Broms
Publication:
Structural Journal
Volume:
106
Issue:
5
Appears on pages(s):
636-645
Keywords:
flat plates; interstory drift; rotation capacity; size effect; unbalanced moment
DOI:
10.14359/51663104
Date:
9/1/2009
Abstract:
A mechanical model is presented for transfer of unbalanced moment caused by imposed rotation of the slab-column connection of a flat plate without shear reinforcement. The failure criterion is based on the limited concrete compression strain capacity of the slab near the column, which previously is found to accurately capture the ultimate deflection and the concurrent punching capacity of concentrically loaded test specimens of varying size and concrete strength. The extended theory for eccentric loading is shown to give good prediction of the ultimate rotation and the concurrent unbalanced moment of test specimens. The theory predicts that the rotation capacity of flat plates decreases with increasing slab thickness, which indicates that recorded seismic drift capacities of test specimens with effective depth less than 125 mm (5 in.) might be unsafe for thicker slabs.