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Nonlinear Analysis of Steel Frames with Semi-Rigid Connections Using the Capacity Spectrum Method.
Deierlein, G. G.; Hsieh, S. H.; Shen, Y. J.; Abel, J. F.
National Center for Earthquake Engineering Research, Buffalo, NY.; National Science Foundation, Washington, DC., July 2, 1991, 92 p.
The report summarizes the development and application of a computer aided system for the inelastic analysis, evaluation, and design of three-dimensional steel frames with semirigid connections under static loading. Main components of the work include: (1) development of a model to represent the nonlinear moment-rotation response of partially restrained connections; (2) development of a matrix-based method for incorporating the connection model in a nonlinear finite element program for framed structures; (3) implementation of the connection model in CU-STAND, a workstation based program for interactive analysis and design of steel framed structures; (4) computer implementation of the capacity spectrum method for estimating inelastic seismic response using modal analysis; (5) demonstration of the system for sensitivity studies on the inelastic respons of a planar frame with semi-rigid connections. Through a case study, overall frame response is found to be relatively insensitive to variations in the connection response parameters. The case study also includes application of the capacity spectrum method to investigate the inelastic limit state under seismic loading and comparisons are made with results based on equivalent static code-based loading.
Dynamic response; Steel structures; Earthquake engineering; Case studies; Loads (Forces); Elastic properties; Structural vibration; Joints (Junctions); Finite element method; Structural members; Moments; Capacity Spectrum Method; Structural analysis; Framed structures; Nonlinear systems; Seismic waves