9526809 Haldar A comprehensive study will be conducted on the inelastic seismic response behavior of steel frames with partially restrained (PR) connections considering all major sources of energy dissipation. The procedure considers as realistically as possible the geometric nonlinearity including the P-delta effect due to drift in the presence of PR connections, material nonlinearity, loading and reloading behavior at the PR connections, and damping. Uncertainty in the parameters will be considered using a nonlinear stochastic finite element algorithm. Reliability analysis will be conducted to generalize the observations made during the experiments and deterministic analyses, and for codification of design. Serviceability requirements consistent with the strength requirements will then be formulated. Several definitions of local, interstory and global ductility will be investigated, particularly for the multiple degree of freedom structures, and the most appropriate definition will be identified. Commonly used steel frames including moment- residing frames, braced frames, dual systems with concentric and eccentric braces will be investigated. Design factors will be re-evaluated and introduced for the seismic design of steel frames with PR connections. The study will complement SAC's Phase II study on seismic analysis of steel framed structures which is funded by FEMA. The project will involve industry trade and associations such as the American Institute of Steel Construction (AISC) and the American Iron and Steel Institute (AISI). ***
