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Copyright of Canadian Geotechnical Journal is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Civil Engineering is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Civil Engineering is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Past major earthquakes have demonstrated that a significant proportion of existing residential buildings are vulnerable to seismic hazards, resulting in economic and social losses. The assessment of earthquake‐induced losses is crucial for devising strategies aimed at enhancing seismic resilience through mitigation plans and emergency response measures. This study intends to provide an analytical methodology for evaluating economic losses for existing residential concrete shear wall buildings in Eastern Canada seismic zones based on Canadian‐compatible seismic capacity parameters. A sampled data set related to residential buildings in Montreal was analyzed and statistical distributions were developed that represent the proportion of buildings in different seismic design code levels and number of stories. Vulnerability analyses were performed, which involved estimating buildings' response under seismic hazard inputs according to the 2020 National Building Code of Canada and conducting loss assessment for structural components, nonstructural displacement‐sensitive components, nonstructural acceleration‐sensitive components, and contents. The results of vulnerability analyses in terms of loss ratio curves showed that the seismic performance varies between mid‐rise and high‐rise concrete shear wall buildings with different seismic design code levels, and nonstructural displacement‐sensitive components exerted the most significant influence on overall economic losses among building components. In addition, a comparison was conducted between Canadian‐compatible economic loss ratio curves and those developed based on the standard seismic capacity parameters in the Hazus technical manual and differences in predicted loss ratios were discussed. The developed loss ratio curves can be integrated into regional scale loss assessment tools for rapid estimation of earthquake‐induced economic losses for concrete shear wall buildings as a function of seismic intensity. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Civil Engineering is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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]

Copyright of Canadian Journal of Civil Engineering is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper summarizes the results from a comprehensive laboratory experimental research program conducted at the University of British Columbia, Canada to study the mechanical behavior of natural fine-grained soils. Constant-volume direct simple shear tests were performed on natural silt samples collected from various locations in British Columbia to investigate the monotonic and cyclic shear loading response of these materials. Influencing factors such as effective confining stress, over-consolidation ratio, initial static shear bias, soil plasticity, and soil fabric/micro-structure on the mechanical behavior of silts were systematically investigated using a series of controlled laboratory tests. The key observations arising from these examinations are presented and discussed to serve as input for the development and/or refinement of design practice approaches for seismic geotechnical design. New directions to be considered to advance the current state of understanding and knowledge on the mechanical behavior of natural fine-grained soils are identified. • Seismic response of natural fine-grained soil was experimentally investigated. • Effect of wide range of physical parameters on the soil behavior was investigated. • Behavioral patterns were explored for a number of different natural soils. • Outcomes were interpreted and translated for potential practice usage. • Findings will contribute to advancement of earthquake engineering design practice. [ABSTRACT FROM AUTHOR]

Highlights • Just-in-time fuel inventories reduce resilience against fuel shortages. • Subduction earthquakes can cause widespread fuel shortages. • Localized fuel shortages after earthquakes are likely in the next 50 years. • A new object-oriented network model was developed to explore resilience scenarios. • Local emergency planners helped improve simulations and build realistic solutions. Abstract An agent-based object-oriented model for the fuel distribution network in coastal British Columbia in Canada is presented. Objects representing infrastructure components with varied attributes and behaviors are described together with objects representing transportation modes on land and on water. A novel feature of the modeling approach is its capacity to represent the diverse nature of the objects in a network. Another novelty of the approach is its capacity to simulate discrete deliveries based on requests, which is a requirement in the modeling of the considered fuel distribution network. This paper presents the software architecture and applies it to assess the probability of fuel shortages following an earthquake for six storage facilities in coastal British Columbia. The results of this assessment can be used to inform emergency response plans. [ABSTRACT FROM AUTHOR]

In performance-based seismic design of a structure, the inelastic deformation demand of structural members or system is the primary input, whereas in conventional design procedure the input is the equivalent static loads to represent seismic effects. The National Building Code of Canada (NBCC) requires that for irregular and buildings higher than 60 m, dynamic analysis must be conducted to calculate seismic design forces and deflection, while for other cases, equivalent static loads can be used for the design. In this paper, the performance of a 20-story steel moment resisting steel frame building, designed for western part of Canada, has been presented. Simulated and actual (scaled) ground motion records are used to evaluate the dynamic response. While NBCC does not provide any performance-based design method, various techniques for displacement-based design have been explored here in the context of the 20-story building. A wide range of variation amongst these methods in terms of their application and results was found. Amongst these methods the direct displacement-based design method seems to be more suitable for carrying out the performance-based design of a building. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Civil Engineering is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Full-scale tests provide valuable information on the characteristics of building structures that can be used to evaluate design methods, to calibrate modelling techniques, and to determine damage corresponding to loading levels. These tests are scarce due to the enormous requirements in testing space and specialized testing equipment. The seismic behaviour of a full-scale, two-storey, reinforced high-performance concrete building designed with moderate ductility detailing is evaluated by pseudo-dynamic testing, during which increasing seismic loads are applied, resulting in increasing levels of permanent damage to the structure. To monitor the level of damage, a series of successive forced-vibration tests are also carried out at each step of the process and are used to track changes in the key dynamic properties of the building. The paper presents the design of the test structure according to the new edition of the CSA A23.3-04 Design of concrete structures standard, the series of pseudo-dynamic tests simulating different levels of earthquake excitation consistent with the 2005 edition of the National building code of Canada, and the evaluation of the performance of the building. It is shown that the detailing requirements of CSA A23.3-04 are more than adequate to provide the ductility and overstrength expected. Les essais à grande échelle fournissent des informations importantes sur les caractéristiques des structures pouvant être utilisées pour évaluer les méthodes de dimensionnement, pour calibrer des techniques de modélisation, et pour déterminer l'endommagement correspondant à des niveaux de chargement. La rareté de ces essais est due principalement à la nécessité de disposer de grands espaces de laboratoire et d'équipements d'essais spécialisés. Dans cet article, le comportement d'un bâtiment en vraie grandeur de deux étages est évalué par essais pseudo-dynamiques dans lesquels le bâtiment est soumis à des niveaux d'excitation sismique croissants causant des dommages de plus en plus importants à la structure. Le bâtiment est construit en béton à hautes performances pour posséder une ductilité modérée. Des essais en vibration forcée sont utilisées pour évaluer les changements dans les propriétés dynamiques de la structure. L'article présente le dimensionnement de la structure d'après la nouvelle édition de la norme CSA A23.3-04, Dimensionnement des structures en béton, la suite des essais pseudo-dynamiques simulant les différents niveaux d'excitation des tremblements de terre consistants avec le Code national du bâtiment du Canada 2005, et l'évaluation de la performance du bâtiment. On montre que les règlements de la norme CSA A23.3-04 sont tout à fait adéquats pour assurer le niveau de ductilité et de surcapacité désiré. [ABSTRACT FROM AUTHOR]

While damping devices can provide supplemental damping to mitigate building vibration due to wind or earthquake effects, integrating them into the design is more complex. For example, the Canadian code does not provide building designs with inline friction dampers. The objective of this present article was to study the overstrength, ductility, and response modification factors of concrete frame buildings with inline friction dampers in the Canadian context. For that purpose, a set of four-, eight-, and fourteen-story ductile concrete frames with inline seismic friction dampers, designed based on the 2015 National Building Code of Canada (NBCC), was considered. The analyses included pushover analysis in determining seismic characteristics and dynamic response history analysis using twenty-five ground motion records to assess the seismic performance of the buildings equipped with inline seismic friction dampers. The methodology considered diagonal braces, including different 6 m and 8 m span lengths. The discussion covers the prescribed design values for overstrength, ductility, and response modification factors, as well as the performance assessment of the buildings. The results revealed that increasing the height of the structure and reducing the span length increases the response modification factors. [ABSTRACT FROM AUTHOR]

In this study, seismic inversion is carried out using a genetic algorithm (GA) as well as a hybrid genetic algorithm (HGA) approach to optimize the objective function designed for the inversion. An HGA is a two steps coupled process, where a local optimization algorithm is applied to the best model obtained from each generation of the GA. The study aims to compare the qualitative as well as the quantitative performance of both methods to delineate the reservoir zone from the non-reservoir zone. Initially, the developed algorithm is tested on synthetic data followed by its application to real data. It is found that the HGA for synthetic data is providing more accurate and high-resolution subsurface information as compared with the conventional GA although the time taken later is less as compared with the former methods. The application to real data also shows very high-resolution subsurface acoustic impedance information. The interpretation of the impedance section shows a low impedance anomaly zone at (1055–1070) ms time interval with impedance ranging from (7500 to 9500) m s−1*g cc−1. The correlation between seismic and well data shows that the low impedance zone is characterized as a clastic glauconitic sand channel (reservoir zone). In seismic inversion using an HGA, one can delineate the areal extent of the reservoir zone from the non-reservoir zone more specifically as compared to the GA-derived impedance. The convergence time of HGA is 4.4 per cent more than GA and can be even more for larger seismic reflection data sets. Further, for a more detailed analysis of the reservoir zone and to cross-validate inverted results, an artificial neural network (ANN) is applied to data, and porosity volume is predicted. The analysis shows that the low impedance zone interpreted in inversion results are correlating with the high porosity zone found in ANN methods and confirm the presence of the glauconitic sand channel. This study is important in the aspect of qualitative as well as quantitative comparison of the performance of the GA and HGA to delineate sand channels. [ABSTRACT FROM AUTHOR]

Structures may predominantly inelastically deform in a single direction during earthquakes and incur greater damage. This behavior is known as seismic ratcheting and can be caused by eccentric gravity loads. Code clauses were introduced in Canada and New Zealand to amplify displacements obtained from static analysis methods to consider seismic ratcheting effects. However, such clauses are based on analyses of reinforced concrete (RC) wall or single‐degree‐of‐freedom (SDOF) structures, and methods to mitigate seismic ratcheting behavior were not explicitly provided. In this study, parametric analyses of steel and RC moment resisting frame buildings were performed to evaluate the adequacy of code clauses, identify parameters which influence seismic ratcheting behavior, and propose methods to mitigate such behavior. It was found that the New Zealand code underestimated the displacement increase for RC buildings, though it was able to envelope the displacement increase for steel buildings while the Canadian code was conservative. Additionally, the displacement increase was found to be sensitive to the building's post‐yield behavior and ground motion properties. However, assumptions of these properties during design may not be reflective of the actual building and seismic conditions, indicating that a reliable estimate of the increase in displacement is difficult to obtain. Instead, employing mitigation measures to reduce seismic ratcheting effects, such as designing to higher seismic demands, adding a secondary structural system to increase the building's post‐elastic stiffness, or providing more balanced lateral strengths after adjusting for eccentric gravity load effects are better measures to counter seismic ratcheting effects caused by eccentric gravity loads. [ABSTRACT FROM AUTHOR]

• Seismic design parameters are proposed for the Moment-resisting Knee-braced Frame. • The study is carried out within the framework of Canadian standards. • All potential hazard sources expected on the Canadian west coast are considered. • The MKF shall be designed as a moderately ductile system. • Overstrength and ductility factors of 1.6 and 3.0 are proposed for the MKF system. • The proposed seismic design parameters are verified by comprehensive nonlinear analyses. This paper proposes and verifies the seismic design parameters, including overstrength-related force modification factor, ductility-related force modification factor, deflection amplification factor, and design period, for the steel Moment-resisting Knee-braced Frame (MKF) system. The building selected in this study is an office located in Vancouver, British Columbia, Canada, in which MKFs act as the lateral load-resisting system. 14 prototype frames spanning a wide range of geometrical configurations are designed following the requirements of the 2015 National Building Code (2015 NBC) of Canada. Nonlinear static analyses are carried out on the prototype frames to determine the preliminary ductility and overstrength factors. Six new MKFs (assessment frames) are designed using the proposed overstrength and ductility factors, and their seismic and collapse performances are examined by comprehensive numerical analyses, considering the effects of the potential sources of ground motion expected on the Canadian west coast, namely subduction intraslab, subduction interface and shallow crustal events. The results of this study suggest that the MKF system shall be designed as a moderately ductile system using overstrength and ductility factors of 1.60 and 3.0, respectively, with a height not exceeding 40 m in regions of high seismicity. [ABSTRACT FROM AUTHOR]

This paper introduces and assesses the seismic and collapse behavior of a new lateral load-resisting system referred to as steel Moment-Resisting Knee Braced Frame (MKF). A design method following the Performance Based Plastic Design (PBPD) procedure is proposed to analyze the structure and size the structural members. A prototype frame part of an office building located in Vancouver, British Columbia, Canada is then selected to demonstrate the design method and evaluate the performance of the proposed system. The prototype MKF is also designed using the conventional elastic approach in accordance with the National Building Code (NBC) of Canada. The seismic performance and collapse response of the proposed system are examined using the nonlinear static analysis, nonlinear response history analysis (NLRHA) and incremental dynamic analysis (IDA) performed on the prototype five-story MKF under potential sources of seismicity in the west coast of Canada including shallow crustal, subduction interface and subduction intraslab events. Fragility curves are finally developed using results of the IDA to obtain the collapse probability of the system. The results of the analyses are compared to those obtained from a steel Moment-Resisting Frame (MRF) counterpart designed in accordance with the PBPD and elastic approaches. Findings of the study show that the proposed steel MKF can efficiently satisfy the code-specified story drift limit and manifest the yielding mechanism assumed in design. The MKF designed according to the PBPD approach offers the lightest structure among all frames studied and yields a collapse probability lower than that of the MKF designed as per the elastic design method. The proposed system can be used in seismic design of steel multi-story buildings as an alternative to conventional steel MRFs. • A new steel lateral load-resisting system referred to as Moment-Resisting Knee Braced Frame (MKF) is introduced. • A Performance-Based Plastic Design method is proposed to design the system. • The seismic performance of proposed MKFs are evaluated and compared to conventional steel MRFs. • Compared to steel MRFs, the proposed MKF offers similar lateral stiffness and collapse behavior with reduced steel tonnage. • MKF can be considered as a viable alternative to conventional steel MRFs in multi-story buildings. [ABSTRACT FROM AUTHOR]

One option to mitigate the seismic risk of highway bridges in Quebec is to replace typical elastomeric bearings used there with natural-rubber seismic-isolator devices. To support this alternative, this paper assesses the seismic vulnerability of typical bridge classes retrofitted with seismic-isolator devices through the development of fragility curves. Retrofitted-bridge fragility curves provide a powerful tool to evaluate the impact of a retrofit measure on the performance of different bridge classes. The analytical fragility approach uses nonlinear time-history analysis with 3-D detailed models for typical configurations of highway bridges. Experimental results of square bearings with different sizes and shape factors are used to account for uncertainties related to the mechanical properties of seismic-isolators. Critical load tests are conducted on slender seismic isolation bearings and a finite-element model is calibrated with the test results to define the seismic-isolator limit states. The fragility curves of different key components of the bridge system are compared and the results reveal that seismic isolation is effective significantly in reducing the probability of damage to columns and foundations. Due to insufficient clearance between the superstructure and abutment wing walls, however, the probability of damage in wing walls is increased and the fragility of this component controls the bridge-system fragility for all bridge classes evaluated. Concrete-girder bridges are found to be more vulnerable than steel-girder bridges due to the larger superstructure mass involved in the seismic response. The results from this work can be used to evaluate and select bridge retrofits, and can form the basis for cost-benefit retrofit studies. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Civil Engineering is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Coupled shear walls (CSW) are an efficient lateral load-resisting system. Their seismic performance depends primarily on their coupling beams (CBs) ability to provide adequate stiffness and strength. However, many existing buildings with CSW resisting system were designed and constructed according to old codes and standards with insufficient requirements for seismic design. These systems feature unsatisfactory behaviour and prematurely collapse in case of major earthquake events. Therefore, their seismic retrofit is urgently needed. The main objectives of this study are, i) evaluate and compare the seismic performance of CSWs designed to old and new codes; ii) highlight the deficiencies of CSWs designed to old codes; iii) investigate a retrofit method using externally bonded (EB) carbon fibre reinforced polymer (CFRP) composites to enhance the seismic response of deficient CSWs. To that end, a 20-story CSW is considered with different design details including one according to old National Building Code of Canada (NBCC) before the 1970s and the other one designed consistent with the new NBCC 2015 and the Canadian Standard Association, CSA A23.3–14, for Eastern seismic Canadian zone. The nonlinear analyses of CSWs under earthquake records are conducted in two steps. At first, the nonlinear time-history analyses of two types of CSWs are carried out using RUAUMOKO program and the deficiencies of old-designed CSW are identified through the comparison of obtained results. In the second step, the old design CSW is retrofitted using CFRP sheets and reanalysed to investigate the benefits of the retrofit technique in mitigating the shortcomings. The results indicate that CFRP retrofitting is an efficient method to enhance the seismic performance of deficient old CSWs in terms of story displacement, inter-story drift, CBs rotation, and ductility demand. [ABSTRACT FROM AUTHOR]

This paper presents an analytical study of the seismic behavior of two different types of industrial buildings; a regular mill-type crane-supporting steel structure and an irregular heavy industrial building housing a vertical mechanical process. For both structures, the seismic response is examined through elastic time-history dynamic analyses in order to validate the predictions from the equivalent static force procedure and the response spectrum analysis method prescribed in current building codes. The analyses also serve to assess the inelastic demand in crane-supporting structure. For the crane-supporting structure, analyses are performed for sites in Montreal and Vancouver in Canada and in Seattle in the United States. The results show that the median horizontal displacement and acceleration from the time-history analyses are generally well predicted by the code analysis methods. Inelastic response in these buildings is likely to develop in the form of buckling of the lower column segment, a failure mode that exhibits limited ductility. For the tall irregular building, the analyses are performed for the Montreal site only. The results show the equivalent static method provides fair displacements estimate, but may lead to unconservative predictions of column and brace forces. Response spectrum analysis method, as prescribed in design codes, appears to provide appropriate prediction of the seismic response of such highly irregular structures. For both building types, a good prediction from response spectrum and time-history analysis methods is possible only when a sufficient number of modes are used. [ABSTRACT FROM AUTHOR]

The seismic provisions of the current edition (2005) of the National Building Code of Canada (NBCC) differ significantly from the earlier edition. The current seismic provisions are based on the uniform hazard spectra corresponding to 2% probability of exceedance in 50 years, as opposed to the seismic hazard level with 10% probablity of exeedance in 50 years used in the earlier edition. Moreover, the current code is presented in an objective-based format where the design is performed based on an acceptable solution. In the light of these changes, an assessment of the expected performance of the buildings designed according to the requirements of the current edition of NBCC would be very useful. In this paper, the seismic performance of a set of six, twelve, and eighteen story buildings of regular geometry and with concrete moment resisting frames, designed for Vancouver western Canada, has been evaluated. Although the effects of non-structural elements are not considered in the design, the non-structural elements connected to the lateral load resisting systems affect the seismic performance of a building. To simulate the non-structural elements, infill panels are included in some frame models. Spectrum compatible artificial ground motion records and scaled actual accelerograms have been used for evaluating the dynamic response. The performance has been evaluated for each building under various levels of seismic hazard with different probabilities of exceedance. From the study it has been observed that, although all the buildings achieved the life-safety performance as assumed in the design provisions of the building code, their performance characteristics are found to be non-uniform. [ABSTRACT FROM AUTHOR]

Abstract: This paper investigates the seismic performance of moment-resisting frame steel buildings with multiple underground stories resting on shallow foundations. A parametric study that involved evaluating the nonlinear seismic response of five, ten and fifteen story moment-resisting frame steel buildings resting on flexible ground surface, and buildings having one, three and five underground stories was performed. The buildings were assumed to be founded on shallow foundations. Two site conditions were considered: soil class C and soil class E, corresponding to firm and soft soil deposits, respectively. Vancouver seismic hazard has been considered for this study. Synthetic earthquake records compatible with Vancouver uniform hazard spectrum (UHS), as specified by the National Building Code of Canada (NBCC) 2005, have been used as input motion. It was found that soil–structure interaction (SSI) can greatly affect the seismic performance of buildings in terms of the seismic storey shear and moment demand, and the deformations of their structural components. Although most building codes postulate that SSI effects generally decrease the force demand on buildings, but increase the deformation demand, it was found that, for some of the cases considered, SSI effects increased both the force and deformation demand on the buildings. The SSI effects generally depend on the stiffness of the foundation and the number of underground stories. SSI effects are significant for soft soil conditions and negligible for stiff soil conditions. It was also found that SSI effects are significant for buildings resting on flexible ground surface with no underground stories, and gradually decrease with the increase of the number of underground stories. [Copyright &y& Elsevier]

• The novel controlled rocking outriggered wall (CORW) is introduced. • CORW is efficiently designed using the novel equivalent energy-based design procedure. • Simulation results show CORW is a reliable system for tall buildings applications. Next-generation earthquake engineering design seeks to develop robust structural systems to limit structural and non-structural damage after strong earthquake shaking. In this study, an innovative high-performance tall building, named Controlled outriggered rocking wall (CORW) system is proposed. The CORW system improves the conventional reinforced concrete (RC) core wall by adding a damped outrigger system and a damped controlled rocking base. The CORW is designed using the novel Equivalent energy design procedure (EEDP) to meet different performance objectives for different shaking intensities. Detailed EEDP for the CORW system is presented in this paper. Three prototype buildings (with 25, 35, and 45 stories) located in Vancouver Canada were designed using the proposed procedure. Robust finite element models of the CORW systems were developed in OpenSees and subjected to a series of nonlinear time history analysis. The results of the nonlinear time history analysis indicate that the CORW system designed using EEDP performs well under different levels of earthquake intensities, where it can be used reliably as an effective seismic force resisting system for high-rise application. [ABSTRACT FROM AUTHOR]

Presents a study that investigated seismic design using the equivalent static load method. Background on approaches in determining seismic load forces; Analysis of the effects of higher modes on base shear; Results and implications for the proposed 2005 edition of the National Building Code of Canada.

Discusses changes in the provisions of the proposed 2005 edition of the National Building Code of Canada regarding seismic loading and design. Seismic hazards in spectral format; Probability of exceedance; Calculation of fundamental periods; Treatment of irregularities; Dynamic analysis requirements.

• Seismic behavior of low- to -high-rise braced modular steel buildings is assessed. • Bi-directional ground acceleration scaled to different hazard levels is considered. • Interstory drift, residual drift, and base shear are the parameters of interest. • Overstrength and ductility modification factors are estimated from pushover analysis. For buildings with repeatable units, modular construction provides an alternative to traditional on-site construction. Modular steel buildings (MSBs) are composed of prefabricated volumetric modules that are produced in a controlled environment such as a factory to be transported and assembled on-site to form a larger, permanent building. Although the studies on the dynamic behavior of modular buildings are limited to up to 10-story MSBs, the recently completed 32-story MSB in New York showcased the applicability of this type of construction beyond mid-rise structures. Additionally, in the National Building Code of Canada both the ductility modification factor and the overstrength modification factor are determined based on the type of the seismic force resisting system, regardless of the building height. Previous studies indicated that neglecting the correlation between these design factors and the height of the building could lead to inadequate design as the building height increases. The current paper assesses the seismic design factors and the seismic performances of 6-, 12, and 32-story MSBs by means of pushover analyses and bi-directional nonlinear time history analyses. The seismic performance is evaluated in terms of interstory drift, residual drift, and base shear. Pushover curves indicated that both overstrength and ductility factors decrease as the height of the building increases. Data from the time history analysis revealed that high-rise MSBs tend to exceed collapse prevention limit and develop column plastic hinges under severe ground motions. On the other hand, the residual drift ratio was found to be more pronounced in low- to mid-rise MSBs. [ABSTRACT FROM AUTHOR]

Southwest British Columbia has the potential to experience large‐magnitude earthquakes generated by the Cascadia Subduction Zone (CSZ). Buildings in Metro Vancouver are particularly vulnerable to these earthquakes because the region lies above the Georgia sedimentary basin, which can amplify the intensity of ground motions, particularly at medium‐to‐long periods. Earthquake design provisions in Canada neglect basin amplification and the consequences of accounting for these effects are uncertain. By leveraging a suite of physics‐based simulations of M9 CSZ earthquakes, we develop site‐specific and period‐dependent spectral acceleration basin amplification factors throughout Metro Vancouver. The M9 simulations, which explicitly account for basin amplification for periods greater than 1s, are benchmarked against the 2016 BC Hydro ground motion model (GMM), which neglects such effects. Outside the basin, empirical and simulated seismic hazard estimates are consistent. However, for sites within the basin and periods in the 1‐5 s range, GMMs significantly underestimate the hazard. The proposed basin amplification factors vary as a function of basin depth, reaching a geometric mean value as high as 4.5 at a 2‐s period, with respect to a reference site located just outside the basin. We evaluate the impact of the M9 simulations on tall reinforced concrete shear wall buildings, which are predominant in the region, by developing a suite of idealized structural systems that capture the strength and ductility intended by historical seismic design provisions in Canada. Ductility demands and collapse risk conditioned on the occurrence of the M9 simulations were found to exceed those associated with ground motion shaking intensities corresponding to the 975 and 2475‐year return periods, far exceeding the ∼500‐year return period of M9 CSZ earthquakes. [ABSTRACT FROM AUTHOR]

Eccentrically braced frame (EBF) is a robust structural system designed for seismic application. The design philosophy for EBF is to utilize the link beams to dissipate the earthquake energy. While such system has been proven to provide sufficient stiffness and strength to prevent the structure from collapse, the structural performance in terms of damage and resilience after strong earthquakes is not explicitly considered. In this paper, a novel design method, named the Equivalent Energy Design Procedure (EEDP), is adopted to design the EBF. EEDP is an alternative design procedure for fused structural systems, where engineers can design the structure to achieve the intended performance objectives at different earthquake hazard levels. To evaluate the performance of the EBF, a 5 storey EBF located in Vancouver, British Columbia, Canada is designed using both the EEDP and the Equivalent Static Force Procedure (ESFP) outlined in the 2015 National Building Code of Canada. Detailed nonlinear dynamic analyses were conducted. The results show that the EEDP designed EBF has better performance with lower initial and repair costs at different levels of earthquake shaking intensities. • A novel performance-based design procedure (EEDP) is adopted to design eccentrically braced frames (EBFs). • Seismic performance assessment of EBFs designed by EEDP and the design method outlined in the National Building Code of Canada (NBCC) is performed. • EBFs designed by EEDP have better performance with respect to resilience and initial repair cost at different earthquake shaking intensities. [ABSTRACT FROM AUTHOR]

• Summary of qualitative and quantitative observations based on full-scale experimental tests. • Ductile slender reinforced masonry shear walls subjected to reversed-cyclic loading. • Comparison of code capacity predictions using experimental data from eight test specimens. • Improved understanding of the seismic response of ductile reinforced masonry shear walls. Ductile slender reinforced masonry shear walls (DSRMSWs) designed and detailed according to modern seismic design provisions, such as those prescribed by the Canadian masonry design code CSA S304-14, are expected to demonstrate ductile performance when subjected to earthquake effects. These walls have shown good energy dissipation characteristics similar to ductile slender reinforced concrete (RC) shear walls and are used as the seismic-force-resisting system (SFRS) for contemporary buildings in Canada and other countries. These walls are usually slender, with clear height-to-thickness (h u /t w) ratios that can exceed 20, and height-to-length (h u /L w) aspect ratios usually greater than 1.5. Experimental studies have shown that the response of DSRMSWs subjected to in-plane simulated seismic loading is often affected by multiple failure modes. The initial failure mode often transitions into other failure modes that may govern the response of the DSRMSWs at high ductility demand levels. It is essential that designers understand the prominent DSRMSW failure modes and how they interact with one another to ensure the adequate seismic performance of DSRMSWs. Seismic design and detailing provisions for DSRMSWs contained in international design codes aim for a ductile, well-controlled flexure-dominant seismic response and preclude the occurrence of undesirable shear-dominant failure modes. However, the interaction between various failure modes is usually only accounted for implicitly. The capacity predictions for DSRMSWs based on in-plane ductile failure modes vary between different masonry design codes in terms of the methodology, complexity level, and material resistance factors. This paper provides a detailed comparison of the capacity predictions from the following international codes: CSA S304-14 (Canada); TMS 402/602-16 (USA); NZS 4230:2004 (New Zealand); and Eurocodes 6 and 8 – EN 1996-1-1:2005/EN 1998-1:2004 (EU). The assessment focuses on the following six in-plane flexure-dominant failure modes: (i) ductile flexure, (ii) shear-flexure, (iii) sliding, (iv) toe-crushing, (v) rocking/bond-slip, and (vi) lateral instability, observed in a series of eight full-scale, fully-grouted DSRMSW specimens tested under reversed cyclic loading. The specimens were characterized by varying h u /L w and h u /t w ratios, the amount and distribution of reinforcement, cross-sectional shape, axial stress level, and type of cyclic loading protocol. The results of this study provide a systematic comparison of the DSRMSW capacity predictions from the different international masonry design codes. [ABSTRACT FROM AUTHOR]

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Copyright of Canadian Journal of Civil Engineering is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Civil Engineering is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The seismic response of tubular steel wind turbine towers is of significant concern as they are increasingly being installed in seismic areas and design codes do not clearly address this aspect of design. The seismic hazard is hence assessed for the Canadian seismic environment using implicit finite element analysis and incremental dynamic analysis of a 1.65 MW wind turbine tower. Its behaviour under seismic excitation is evaluated, damage states are defined, and a framework is developed for determining the probability of damage of the tower at varying seismic hazard levels. Results of the implementation of this framework in two Canadian locations are presented herein, where the risk was found to be low for the seismic hazard level prescribed for buildings. However, the design of wind turbine towers is subject to change, and the design spectrum is highly uncertain. Thus, a methodology is outlined to thoroughly investigate the probability of reaching predetermined damage states under any seismic loading conditions for future considerations. La réponse sismique des tours d'éoliennes en tubes d'acier est une question importante puisque ces dernières sont de plus en plus installées dans zones sismiques et que les codes de calculs ne traitent pas clairement de cet aspect de la conception. Les aléas sismiques sont ainsi évalués pour l'environnement sismique canadien en utilisant une analyse implicite par éléments finis et une analyse dynamique incrémentielle pour une tour d'éolienne de 1,65 MW. Son comportement sous une excitation sismique est évalué, les dommages sont définis et un cadre est établi pour déterminer la probabilité de dommages à la tour à différents niveaux d'aléas sismiques. Les résultats de l'implantation de ce cadre en deux endroits au Canada sont présentés, où le risque était faible pour le niveau d'aléas sismiques prescrit pour les bâtiments. Toutefois, la conception des tours d'éoliennes est sujette à changement et la plage de conception est très incertaine. Ainsi, une méthode est présentée afin d'examiner en détail la probabilité d'atteindre des niveaux de dommages prédéterminés sous des conditions de charge sismique possibles dans l'avenir. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Civil Engineering is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Civil Engineering is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Presents a study that examined the provisions of the 1995 National Building Code of Canada (NBCC) with regard to the elastic response of simple asymmetric building models to earthquake motions. Background on the torsion provisions of the 1995 NBCC; Analysis of the torsional response of the single-story building model; Results and implications.

Examines dynamic analysis procedures for the computation of seismic design forces. Categories of dynamic analysis procedures; Information on the seismic provisions of the 1995 National Building Code of Canada; Details of the determination of the structural period to be used in association with the equivalent static force method.

Examines the provisions of the proposed 2005 edition of the National Building Code of Canada for earthquake load and effects on structures. Aim of the proposed provisions; Details of the inclusion of soil effects in the provisions; Examples of calculations for typical multi-story buildings in Canada.

Provides information on the provisions of the proposed 2005 edition of the National Building Code of Canada regarding earthquake-resistant design. Requirements for complete load paths; Definitions of irregular structures and special design requirements associated with the irregularities; Importance of the effects of displacements.

Examines proposed changes to the 2005 edition of the National Building Code of Canada regarding seismic force modification factors. Background on developments in the base shear equation for seismic design; Analysis of several approaches in determining force modification factors; Results and implications.

Presents a study that examined foundation factors in seismic codes to capture the amplification effects of local soil conditions on ground motions. Review of developments in categorizing site conditions for seismic codes; Analysis of approaches to foundation factors; Implications of the results for the proposed 2005 edition of the National Building Code of Canada.

This study evaluates the seismic response of an advanced hybrid steel‐timber structure using a nonlinear static and dynamic analyses. A three‐story prototype building located in Vancouver, BC, Canada was designed first. The gravity load resisting system (GLRS) consists of cross‐laminated timber (CLT) floor slabs, glulam beams, and glulam columns. The lateral load resisting system (LLRS) includes a chevron‐type steel Concentrically Braced Frame. The numerical model of the structure was then developed in the OpenSees program. Nonlinear hysteresis response of steel braces and timber joints were explicitly simulated. The results of the analysis revealed that the hybrid structure possess an acceptable lateral stiffness while providing sufficient ductility to dissipate seismic energy. No unsatisfactory response was observed in the timber system. [ABSTRACT FROM AUTHOR]