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It has been observed during previous earthquakes that the damage to operational and functional components of buildings often result in more injuries, fatalities and property damage than those inflicted by structural damage. Operational and functional components of a building include architectural components, mechanical and electrical equipment, as well as building contents. A rational approach to designing these elements against seismic excitations involves the use of floor design spectra. The development of such design spectra for buildings in Canada constitutes the objective of the paper. This objective was achieved by conducting comprehensive analyses of selected reinforced concrete buildings, with different lateral force resisting systems and building heights, under code compatible earthquake records for an eastern and a western Canadian city. It was observed that the floor response was significantly amplified, especially for buildings with short periods. Generally, the higher floors showed higher amplifications with differences in spectra between the floors being more pronounced in low-rise buildings and shear wall buildings with short fundamental periods. The results provided a large volume of data to generate floor response spectra for the design of operational and functional components of buildings in Canada. The details of the approach and the design spectra are presented in the paper. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to provide a summary of the evolution of seismic design in Canada. This paper presents the significant changes to the approach taken in determining seismic hazards and seismic hazard maps, and describes the evolution of the seismic design provisions of the National building code of Canada. The introduction of important parameters in determining the seismic base shear such as the period of vibration of the structure, the influence of type of soil, and the concepts of ductility and energy dissipation capacity of elements and structures are presented. The levels of seismic design base shears, determined from different versions of the National Building Code of Canada, are compared for reinforced concrete frame and wall structures to illustrate the changes. L'objectif de cet article est de présenter un sommaire de l'évolution de la conception parasismique au Canada en se référant aux modifications des efforts sismiques prescrits par le Code National du Bâtiment du Canada. Les changements majeurs concernant l'aléa sismique et les cartes sismiques correspondantes qui ont été créées sont présentés. On présente également les paramètres importants, qui influencent le calcul sismique de l'effort tranchant à la base, tels que la période de la structure, l'influence du type de sols, les concepts de ductilité et de dissipation d'énergie. La variabilité du niveau des charges sismiques, pour les différentes versions du Code National du Bâtiment du Canada, est présentée pour les cadres en béton et les refends, afin d'illustrer ces changements. [ABSTRACT FROM AUTHOR]

Single-storey braced steel frame buildings (SSBSFs) are currently the most widely used commercial structures, which include strip malls, power centres, warehouses, small and medium-sized industrial plants. The lateral seismic or wind forces acting on such low-rise structures are usually transferred from a metal roof-deck diaphragm to a system of vertical bracing members. Because these flexible roof diaphragms have a considerable effect on the dynamic response of SSBSFs during an earthquake, they also play an important role in the evaluation of the fundamental vibration period, a key parameter in determining the magnitude of the design seismic forces. It is therefore of utmost importance to reliably predict the fundamental period of SSBSFs. This paper presents the results of a four-year field measurement research project on the dynamic behaviour of SSBSFs. The goal of the project was to create a reliable database for the dynamic characteristics of SSBSFs (periods, mode shapes, and damping) and to find a relationship between them and the geometric parameters (height and plan dimensions). The field tests are described, along with the selected buildings and experimental setup. The measured fundamental periods are then compared to the National building code of Canada (NBCC) empirical equations. A statistical analysis of the data, based on different regression models, yielded new proposed building geometric parameters to be used in simple equations for the prediction of the fundamental period of SSBSFs. [ABSTRACT FROM AUTHOR]