Evaluation of Displacement - Based Analysis and Design Methods for Steel Fraemes with knee element

This report investigates the use of displacement – based methods of analysis in the design of frames incorporating knee passive dissipative element. An extensive analysis and design study of 3,6 and 10 storey frames, both undamped moment-resisting frames (MRFs) and retrofitted with dissipators has been performes. Frames were modeled using the finite element program sap 2000 and were analysed using both non-linear static pushover analysis and non-linear time history analysis. The principal aims were to assess the degree of improvement in performance achieved through use of the devise , and the suitability of various displacement – based analysis methods for estimating the seismic response of frames fitted with dissipative devices. Pushover analysis were found to be a useful design tool for the unretrofitted frames, giving good estimates of the overall displacement demands , base shears plastic hinge formation However, the various pushover approaches proved less successful at estimating the performance of the dissipative frames, where they appeared to underestimate the beneficial effects of energy dissipation. Of the various pushover methods assessed, the FEMA 356 approach appears to offer the most accurate and realistic estimate of seismic performance, with the exception of the inter-storey drift distribution.

کلیدواژه ها:

Displacement Based Design ، Pushover methods ، knee element