The Restrained Long Concrete Column as a Part of a Rectangular Frame
John E. Breen and Phil M. Ferguson
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This investigation was concerned with the long tied column as part of a building frame. The column was directly loaded axially while a beam supplied a moment loading in such a manner that the far end of the column was restrained against rotation, but was not completely fixed. Short-time loading to failure was used for five frames. A single test under 90 day sustained load followed by loading to failure was included. At a nominal eccentricity of 0.3 of the column thickness, there was no long column strength reduction. At an eccentricity of 0.1 of the column thickness there was no long column strength reduction at an h/l of 15 but at an h/t of 30 there was a 3 percent reduction for one speci-men and 8 percent for another. The longer columns were considerably relieved of their moment loading by virtue of their reduced stiffness at higher loads. The shorter columns were greatly shielded by compression hinging at their loaded end.