MODELE DE RESISTANCE POUR LES POUTRES CELLULAIRES ANGELINA EN ACIER ET MIXTES

摘要

A new type of cellular beams fabricated from hot rolled profiles appeared recently, which is named Angelina. Its openings come from a cutting following a sinusoidal shape. These beams are used either for steel or composite structures and they allow rectangular ducts, even with large dimensions, to pass through their openings. They can thus lead to a substantial reduction of the floor thickness and in fine they contribute to increase the competitiveness of steel buildings. The very aesthetic shape of the openings is also an advantage that can be underlined to improve the architectural attractiveness of steel frames. To take benefit from these possibilities, accurate design methods are required: that's why ArcelorMittal asked to CTICM to carry out studies about the static behaviour of Angelina beams. This paper presents the results of 4 tests (on 3 steel beams and 1 composite beam) and of 280 numerical simulations carried out to determine ultimate loads and failure modes, under the simultaneous effects of bending and shear. A new analytical design method is then proposed, for the resistance of Angelina beams taking into account the Vierendeel effect. This new model can be used inside the range of the geometrical and mechanical scope exposed as an introduction. Finally the comparison of the ultimate loads according to this new model and according to the reference database (experimental or numerical data) is provided to assess the safety and accuracy of the proposed expressions.