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Traditionally, initial material cost has been the governing factor for material selection in structural construction. However, the growing maintenance cost of existing infrastructure has demanded a long-term vision in material selection and in this regard, life cycle cost assessment has been proven to be a better assessment tool than the initial cost of construction. Despite its higher initial cost, aluminum offers many positive attributes, such as a high resistance to weight ratio, good recyclability, and excellent corrosion resistance, which can significantly reduce the life cycle cost of a structure over its entire service life. Yet, the limited use of aluminum in bridge construction and the lack of literature on this matter do not provide comprehensive evidence of its superior performance in the long-term. Based on this premise, this study performs a life cycle cost analysis on the first all-aluminum bridge situated in Arvida, Quebec. The analysis has revealed that most maintenance costs are associated with the rehabilitation of the concrete deck. The frequent concrete deck maintenance dismisses the benefits of the low maintenance aluminum structure. In order to investigate further, an alternative analysis has also been performed on the bridge with a hypothetical aluminum deck that replaces the existing concrete deck. The comparison shows that the aluminum deck reduces the maintenance cost significantly. However, further analysis should be performed with an optimized aluminum deck that can also yield a significantly lower life cycle cost compared to the existing bridge. [ABSTRACT FROM AUTHOR]

Aluminium alloys exhibit a non-linear stress--strain material response with significant strainhardening effects. Whereas the latter shall be considered in the design of aluminium elements, they are largely ignored in most design codes, such as Eurocode 9 and the Canadian Standards. Preliminary studies on typical aluminium I-shapes indeed indicated that as much as 40% extra resistance could be reached through more accurate and appropriate design recommendations. Accordingly, an original design approach based on the Overall Interaction Concept (O.I.C.) is developed to better account for the actual behaviour of aluminium structural shapes. In this respect, non-linear finite element models are developed within ABAQUS and further validated against experimental data. Subsequently, comprehensive parametric studies are performed to collect numerical reference results, and comparisons are performed with resistance predictions from well-known design standards. The performance of the newly developed O.I.C.-based design approach is shown to significantly improve accuracy, safety, consistency, and reliability levels. [ABSTRACT FROM AUTHOR]

This paper investigates the ultimate resistance of aluminum circular hollow sections (C.H.S.) under simple load cases as affected by local buckling and material strain hardening. Following the development of advanced non-linear shell finite element models and their validation against existing test data, extensive non-linear numerical analyses were carried out, varying several key parameters such as alloy types, load case (compression or pure bending) and various section dimensions. The numerical results are used as references to analyze the structural performance of aluminum C.H.S., and to assess the accuracy of design equations based on the Overall Interaction Concept (O.I.C.). The O.I.C.-based proposal is shown to yield more accurate, consistent, and continuous resistance predictions than Eurocode 9 recommendations. [ABSTRACT FROM AUTHOR]

Aluminum appears as a promising structural material as it shows many benefits such as a great strength to weight ratio, low maintenance costs, resistance to corrosion, recyclability, etc. Accordingly, characterizing the behavior and resistance of different aluminum sections under various loading conditions is essential. The current paper presents an experimental investigation on aluminum sections with simple and complex geometries to study the effect of cross-section shape on the buckling response of the aluminum sections. Firstly, eight tensile coupon tests were conducted on coupons of aluminum alloy 6061-T6 to accurately determine its material properties. Geometrical imperfections on the surface of each specimen were then measured using a 3D scanner. Further, eight stub column tests were also performed to study the behavior of I, H and complex cross-sections under pure compression. In addition to this, 12 cross-section tests under combined compression and bending are currently under way to study the buckling behavior of these specimens under eccentric compression. [ABSTRACT FROM AUTHOR]

Aluminum has a bright future as a structural material due to its excellent corrosion resistance, durability, lightweight, and complete recyclability. However, it is necessary to fully understand its mechanical behaviour under various loading conditions to make it competitive with other materials, such as concrete or steel, for civil engineering applications, especially as primary load-bearing structural members. To develop an in-depth knowledge on the behaviour of extruded aluminum sections of various shapes, an extensive experimental study was undertaken with specific emphasis on analyzing the buckling response of rectangular and square hollow sections (RHS and SHS) with 6061-T6 aluminum alloy under compressive loads. In this regard, six stub column tests were performed under axial compression, while eleven short beam-column tests under eccentric compression are currently in progress. Additionally, six tensile coupon tests were performed to obtain the full material stress--strain curve, and initial geometrical imperfections were measured mechanically and using a 3D scanner. Finally, the results of the stub column tests were compared to the resistances calculated using the Canadian standard CSA S157, which were generally conservative compared to the experimental observations. [ABSTRACT FROM AUTHOR]

The behaviour of so-called 'cellular members' against lateral torsional buckling is investigated. These beams comprise regularly spaced web openings, and are especially used for their high resistance-to-weight ratio, the possibility of integrating service pipes within their height, and for aesthetic reasons. Such profiles usually exhibit a complex behaviour and many potential failure modes, including interactional local/global instability modes. Regarding global instability, members are usually designed by means of approximate design rules, which often lead to an unduly conservative girder, with beams sometimes showing up to 150% resistance reserve. This research work aims at improving this situation, through development of adequate design formulas. Both experimental and extensive numerical parametric studies are undertaken; a series of three full-scale tests is first performed, with the intention of using them to validate the derived finite-element models. Because the numerical models show very good agreement with the tests, they are then further used to gather a large set of numerical reference results where many parameters are varied: relative slenderness, steel grades, cross-sectional dimensions, bending moment distributions and the relative size of the openings. Finally, a new set of dedicated design rules is derived, which is demonstrated to be accurate and economic while leading to safe estimates of resistance when compared to all reference results. [ABSTRACT FROM AUTHOR]