DEVELOPMENT OF A FINITE ELEMENT MODEL OF STEEL-CONCRETE COMPOSITE ALVEOLAR BEAMS

Resumo

The use of steel-concrete composite beams allows the best properties of these materials to be
explored, enabling the design of larger spans and the achievement of more economical structural
solutions. The alveolar steel beams, in turn, provide a greater rationalization in the use of this material,
since, with almost the same amount of steel, expanded profiles are produced with greater moment of
inertia and, consequently, greater flexural strength and better performance under serviceability limit
states. Through the union of these structural systems the composite alveolar beams are obtained, in
which the advantages of the two systems are enhanced, and their disadvantages are mitigated. Thus, it
is possible to reduce materials consumption and, consequently, the generation of environmental impacts.
Considering that the Brazilian and the international standards do not specify criteria for analysis and
design of composite alveolar beams, numerical and experimental studies have been carried out at the
academic level in order to deepen the understanding about the behavior of these structures, whose
complexity involves the occurrence of different modes of collapse. The present work aims to contribute
to the advances in the field of numerical analysis of composite alveolar beams by developing a finite
element model with ANSYS software, version 19.2, in which the steel profile was modeled by shell
elements, the concrete slab by hexahedral solid elements, the connectors by non-linear spring elements,
the steel deck sheet by shell elements and the slab reinforcement bars by embedded elements. In order
to capture the effects of local instabilities, initial geometric imperfections were added to the profile
through the combination of buckling modes. For the simulation of concrete behavior, two models have
been used: the first, denominated DP-Concrete, is a native ANSYS model, available in the more recent
versions of this software; and the second, denominated usermat, is a customizable model based on
Ottosen criterion. The validation of the model was done through the numerical analysis of beams tested
experimentally by other authors. The obtained results presented a good correlation with the experimental
results and with numerical results from previous works.