US-TAIWAN COLLABORATIVE RESEARCH ON STEEL COLUMN THROUGH CYCLIC TESTING OF TWO-STORY SUBASSEMBLAGES
Journal
World Conference on Earthquake Engineering proceedings
Journal Volume
2021
Start Page
2i-0213
ISSN
30065933
Date Issued
2021
Author(s)
Abstract
Recent studies showed that the seismic performance of steel columns is affected by the boundary conditions at both ends of the member. To reflect realistic boundary conditions, five half-scale, two-story steel subassemblage frames with a single column and steel beams at two floors were tested to evaluate the cyclic behavior of steel columns. The prototype design was based on a seven-story apartment building in Taiwan. The building is a dual system with a special moment-resisting frame (SMRF) and a buckling-restrained braced frame (BRBF). Three subassemblages (Specimens HC-37, HC-37-R and HC-49) used H-shaped columns of SN490B steel, the difference being that the web depth-to-thickness ratio (=49) of the last specimen was higher than that (37) of the first two specimens. The remaining two subassemblages (Specimens HBC-12 and HBC-16) used built-up box columns of SM570M steel; the wall width-to-thickness ratios were 12 and 15.7, respectively. The same built-up I-shaped beams of SN490B steel with a Reduced Beam Section (RBS) were used for all five subassemblies. A constant axial compression force ranging from 20 and 40% of the column yield force was applied to the column; the top end of the column was cyclically loaded with a sequence of increasing lateral drifts. Test results showed that the realistic boundary condition at the top end of the first-story column significantly altered the moment distribution along the column height; such distribution was further affected by the column buckling at the bottom end. The H-shaped columns experienced much significant local buckling and axial shortening than the built-up box columns. The highly ductile member requirement in AISC 341 cannot assure a satisfactory seismic performance of the two H-shaped columns at a story drift angle of 0.04 rad, which is not the case for built-up box columns.
Subjects
Built-Up Box Column
Column Inflection Point
H-Shaped Column
High-Strength Steel
Two-Story Subassemblage Frame Test
Publisher
International Association for Earthquake Engineering
Type
journal article