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Investigation of the Nonlinear Characteristics of a Three Story Steel Frame Using System Identification.
Kaya, I.; McNiven, H. D.
National Science Foundation, Washington, DC., December 1978, 97 p.
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In the study reported here, two mathematical models were constructed of a three-story steel frame that are meant to predict its responses to seismic disturbances. This is an extension of work previously reported, devoted to the construction of mathematical models of the same frame to predict its linear response. The models constructed in this work are meant to predict nonlinear response. This extension consists of accounting both for changes in the damping coefficients when the amplitudes of motion are large, and for yielding by including the hysteretic behavior of the ends of the members. Perhaps the most important decision in this extension has been the choice to model the hysteretic relationship between the bending moments and rotations at the ends of the members. With the introduction of hysteretic material behavior, three parameters are added to the eight which are a carry-over from the linear model, so that the new nonlinear models contain eleven parameters. Both of the models predict the experimental time histories of the floor translations and joint rotations extremely accurately, with the advantage going slightly to the first model.
Dynamic response; Systems identification; Computer programming; Buildings; Earthquake engineering; Earthquake resistant structures; Mechanical hysteresis; Seismic design; Frames; Nonlinear analysis; Steel construction; Mathematical models