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Generalized Plastic Hinge Concepts for 3D Beam-Column Elements.
Chen, P. F. S.; Powell, G. H.
National Science Foundation, Washington, DC., November 1982, 277 p.
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In the section type of model, inelastic behavior is defined for the cross section as a whole, rather than for individual fibers. Action-deformation relationships for the cross section must be devised, considering the stress-strain characteristics of the cross section material. Models of this type are less accurate than fiber models, but more efficient computationally. This report presents the theory and computational techniques for the section type of model and analyzes five example structures. In developing the model, inelastic interaction between bending moments, torque and axial force has been considered by means of yield interaction surfaces and a flow-rule type of plasticity theory. Emphasis has been placed on the ability to consider arbitrary loading-unloading cycles of the type likely to be induced by an earthquake. Both stable hysteretic action-deformation characteristics and relationships involving stiffness degradation are considered.
ANSR computer program; WIPS computer program; Beams (Supports); Mechanical hysteresis; Earthquakes; Computer applications; Columns (Supports); Dynamic loads; Framed structures; Stiffness methods; Dynamic structural analysis