Behavior of End-Plate Connection with Oversize Holes and Plate Washers for Column Splice

This study investigated the behavior of end-plate connections for column splices with construction tolerance. To adjust misalignment between upper and lower columns, oversize holes were drilled on the end plate and plate washers were then placed to bridge over the oversize holes under the head or nut. Six columns with the misaligned connection in the plastic hinge region were tested under cyclic loads. Test variables considered were misalignments, end-plate details (i.e., thickness and stiffener), and the flexural capacity of columns. The test results showed that although plastic deformations occurred significantly near the connection with misalignment, the connection performance of the columns was good: prying action and plate deformation at the connection were minimized although the connection strength of the end plate was only 60% of the required strength because the plate washers provided additional resistance. In addition, slip deformation on the faying surface was negligible due to the preloads of fully tightened bolts. The stiffened end plate was effective in reducing the required thickness of end plate, whereas the shim plate between the top and bottom end plates slightly degraded the slip resistance. The force-transfer mechanism at the end-plate connection under axial compression was investigated and verified through finite-element analysis.