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This paper evaluates the overstrength, ductility, and response modification factors for low to mid-rise buckling restrained braced frames (BRBFs) designed as per the 2010 National Building Code of Canada. In addition to nonlinear static pushover analyses, dynamic time history analyses are performed to assess the seismic performance of four-, six-, and eight-story BRBFs. Different bracing configurations, including chevron (inverted-V) and split-X braces, are considered for the building frames with varied frame span lengths of 6 m and 8 m. The results confirm that the prescribed design values for overstrength and ductility factors provide reasonable estimations of the lower bound for these factors. The response modification factor obtained in this study ranged from 4.8 to 6 for different frames. The results also indicate that the response modification factor decreases with the increase of story height and span length. Moreover, bracing configurations may slightly affect the response modification factor for BRBFs. [ABSTRACT FROM AUTHOR]

In this paper, the seismic performance of 1970s regular R/C bridge is investigated in terms of ductility demand, considering site-specific time histories and the amplification effect of soil with heterogeneous stratigraphy. The five seismic site classes of the 2005 National Building Code of Canada were used in this study and seismic site analyses were performed on soil columns representing real stratigraphies of typical Quebec City soil profiles. A total of 24 linear modal dynamic analyses and 24 nonlinear time-history analyses were performed using historical earthquakes representative of Eastern Canada. It was found that the bridge model shows yielding at the base of the columns for site classes C, D, and E. For site classes D and E the 2005 NBCC amplification factors were found to underestimate the amplification effect on the bridge's response. These results also show that the energy dissipation is a better indicator of damages than the permanent displacement. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive review of the new provisions for the design of coupled shear walls in Canadian seismic zones. It follows major revisions that were incorporated in the National Building Code of Canada 2005 (NBCC 2005) and in the Canadian standard Design of concrete structures (CSA A23.3-04), which were due, in particular, to the adoption of a new Canadian map of seismic risk. The present study is intended to address recurring confusions in current practice and the difficulties expressed in the application and interpretation of the new NBCC 2005 and CSA A23.3-04 provisions. A design flowchart is thus proposed as a practical guide, describing, step by step, the required verifications at each stage of coupled shear walls calculation. Finally, to demonstrate the applicability of these new provisions, a numerical example is detailed, following the presented design flowchart. [ABSTRACT FROM AUTHOR]