Limit states design of semi-rigid frames using advanced analysis: Part 2: Analysis and design

Abstract

This paper presents an integrated advanced inelastic analysis method for proportioning semi-rigid steel frame structures in which the beam-to-column connections are composed of angles. The modeling of connection moment-rotation curves and their classifications have been presented and discussed in a companion paper. An approach called the second-order refined plastic hinge analysis is introduced. The method is validated by comparing the results with those obtained based on a more exact plastic zone analysis. It is shown that the refined plastic hinge analysis provides a good representation of inelastic behavior, and that it enables the full assessment of system and member inelastic behavior up to the limit state of strength. This analysis method is used to assess the adequacy of a two-dimensional semi-rigid frame, and its members and connections in resisting the factored load effects. The design is evaluated with respect to the system's strength and serviceability limit states, including conformance with the code requirements for strength and stability of individual members, and rotation capacity of connections. The inclusions of connection nonlinear effects in advanced inelastic analysis provide a straightforward task for proportioning of frame members and connections, thus avoiding the complexity of having to perform specification member capacity checks for individual frame members. © 1993.