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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 Canadian highway bridge design code (CHBDC) contains provisions for designing concrete members with fiber-reinforced polymer (FRP) reinforcement. In the second edition of the code, new shear design procedures for FRP-reinforced sections are provided. These procedures are consistent with those for steel-reinforced members in the code, in consideration of some modifications that account for the substantial differences between FRP and steel reinforcement. The shear approach adopted in the CHBDC follows the traditional approach of Vc + Vs for shear design. This paper presents an evaluation of this approach by comparing it with experimental shear strengths of available test data on beams longitudinally reinforced with FRP bars and with or without FRP stirrups. In addition, the CHBDC approach was compared with the FRP shear design provisions currently in effect in North America using the available test results. The comparison shows that the CHBDC method significantly underestimates the shear strength of FRP-reinforced concrete beams. A proposed modification to this method is presented and verified against available test results. Le Code canadien sur le calcul des ponts routiers (CCCPR) contient des dispositions pour la conception de membres de béton avec armature en polymères renforcés de fibres (PRF). Dans la 2e édition du code, de nouvelles procédures pour la conception de cisaillement pour les sections armées de PRF sont fournies. Ces procédures sont compatibles dans le code avec celles des membres armés d'acier en considérant certaines modifications pour tenir compte des différences substantielles entre les armatures en PRF et en acier. L'approche du cisaillement adoptée dans le CCCPR suit l'approche traditionnelle de Vc + Vs pour la conception du cisaillement. Cet article présente une évaluation de cette approche en la comparant à des forces de cisaillement expérimentales dans des données de test disponibles sur des poutres armées longitudinalement de barres de PRF, et sans ou avec étriers de PRF. En outre, l'approche du CCCPR a été comparée aux dispositions de conception de cisaillement PRF actuellement en vigueur en Amérique du Nord en utilisant les résultats de tests disponibles. La comparaison montre que la méthode du CCCPR sous-estime significativement la résistance au cisaillement des poutres armées en PRF. Une proposition de modification de cette méthode est présentée et vérifiée par rapport aux résultats des essais disponibles. [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.)

During the past decade, composite steel-free deck bridges came to reality in Canada through the construction of five bridges. The new structural system enables the construction of a concrete deck that is totally devoid of all internal steel reinforcement. Traditionally, reinforced concrete bridge decks are designed to sustain loads in flexure. The steel-free deck bridge system develops internal compressive forces "internal arching," which leads to failure by punching shear at substantially higher loads than the flexural design load. The fibre-reinforced concrete deck is usually attached to the steel girders through flexible shear connectors. These steel girders are transversely tied together by steel straps and cross frames. In this paper, the concept of the new bridge system is briefly discussed. The generations of the deck slabs are introduced. Brief outlines of the bridges built to date with this new technology are presented. A three-dimensional finite element model is then proposed to study the behaviour of the main structural component of the new system. The model is verified against previous experimental results and is used to perform a parametric study on some aspects which are thought to significantly affect the behaviour of the new steel-free deck bridge system.Key words: bridges, composite girders, finite element method, steel-free deck, steel straps.Durant la dernière décennie, les ponts à tablier composé sans acier sont devenus réalité au Canada grâce à la construction de cinq ponts. Ce nouveau système structural permet la construction d'un tablier en béton qui est complètement dépourvu de tout renforcement interne en acier. Traditionnellement, les tabliers de pont en béton armé sont conçus afin de supporter des charges en flexion. Le système de tablier de pont sans acier développe des forces internes en compression « cintrage interne » et résulte en une rupture par poinçonnement en cisaillement pour une charge substantiellement plus grande que les charges en flexion de conception. Le tablier en béton renforcé de fibres est habituellement attaché aux poutres d'acier à l'aide de connexions de cisaillement flexibles. Ces poutres d'acier sont attachées ensemble transversalement à l'aide de liens d'acier et de contreventements. Dans cet article, le concept de ce nouveau système est brièvement discuté. Les générations des tabliers en dalles sont introduites. Un bref aperçu des ponts construits à ce jour avec cette nouvelle technologie est présenté. Un modèle par éléments finis tirdimensionnel est par la suite proposé afin d'étudier le comportement des composants structurels principaux du nouveau système. Le modèle est confronté aux résultats expérimentaux obtenus par d'autres dans le passé. Ensuite, il est utilisé afin de performer une étude paramétrique sur quelques aspects qui sont suspectés d'affecter de façon significative le comportement de ce nouveau système de tablier de pont sans acier.Mots clés : ponts, poutres composées, méthode par éléments finis, tablier sans acier, liens d'acier.[Traduit par la Rédaction] [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.)

Discusses the use of fibre-reinforced polymer (FRP) rods in bridge deck slabs. Requirements of the Canadian Highway Bridge Design Code Clause 16.8.7 on concrete deck slabs; Key to the arching action of a deck slab; Orientation of transverse reinforcement; Information on temperature-induced strains in FRP.

This article focuses on the new Canadian Highway Bridge Design Code, the design provisions for fiber-reinforced structures. The Canadian Highway Bridge Design Code Technical Subcommittee 16 on Fiber Reinforced Structures has been investigating the level of conservatism in the shear equation as part of its continuous work in the calibration of the design provisions for fiber-reinforced polymer structures. Internal committee documents have been produced dealing with developments of a reliability-based health monitoring system for fiber-reinforced structures.

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.)

Dynamic characteristics of the Confederation Bridge were determined from recorded accelerograms of vibrations due to traffic and wind. Natural frequencies of four vertical and five transverse modes of the bridge were identified from the Fourier amplitude spectra of the accelerograms. By appropriate filtering and processing of the accelerograms, displacement time histories of vibrations associated with each of these modes were computed, which were used to determine the mode shapes of the bridge. These characteristics are essential for investigations of the dynamic performance of the bridge. The computed natural frequencies are significantly larger than those of the finite element model used in the design of the bridge. Since the dynamic effects due to traffic, wind, and seismic loads depend on the natural frequencies of the bridge, an evaluation study of these effects is needed using the natural frequencies and mode shapes obtained from measured vibrations.Key words: bridge, acceleration, displacement, record, vibration, filtering, frequency, mode, Fourier spectrum.Les caractéristiques dynamiques du pont de la Confédération ont été déterminées à partir d'enregistrements d'accélérations causées par les vibrations dues à la circulation et au vent. Les fréquences fondamentales de quatre modes verticaux et de cinq modes latéraux du pont ont été identifiées à partir de l'amplitude des spectres de Fourier des accélérations enregistrées. Avec un filtrage et un traitement appropriés des accélérations enregistrées, les historiques de temps des déplacements des vibrations associés à chaque mode ont été calculés, lesquels ont été utilisés afin de déterminer les modes propres du pont. Ces caractéristiques sont essentielles afin d'investiguer les performances dynamiques du pont. Les fréquences fondamentales calculées sont significativement plus grandes que celles du modèle d'éléments finis utilisé pour la conception du pont. Puisque les effets dynamiques causés par la circulation, le vent et les charges sismiques dépendent des fréquences fondamentales du pont, une évaluation de ces effets, utilisant les fréquences fondamentales et les modes propres obtenus à partir de vibrations mesurées, est requise.Mots clés : pont, accélération, déplacement, enregistrement, vibration, filtrage, fréquence, mode, spectre de Fourier.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]