Experiments on Restrained Columns Permitted to Sway. Strength of Beam-And-Column Subassemblages in Unbraced Multi-Story Frames

摘要

Experiments were conducted on full-scale restrained columns permitted to sway in order to study their lateral-load versus sway-deflection behavior with a variable rotational restraint stiffness. These tests also provided experimental verification of some aspects of the sway subassemblage method of analysis. Three restrained columns were tested, simulating the restrained columns in a windward, an interior and a leeward sway subassemblage. The column axial load ratio for all the restrained columns was maintained constant at 0.7. Each test specimen consisted of one column and one or two restraining beams welded to the column. The rotational restraint stiffness of restrained column varied during the test due to the formation of a plastic hinge. The test results show good agreement with the predictions from restrained column theory. (Author)