HIERARCHICAL MODELING OF SHEAR-WALLS STRUCTURES

Resumo

The consideration of the horizontal displacements and forces produced by lateral actions
such as wind or earthquake is mandatory for tall buildings. In order to reduce the effects generated by
bending and twisting of the building, structural systems known as "bracing" are used. As examples of
these systems, there are frames and shear-wall elements; this last one, usually located inside the
buildings, with a small thickness when compared to the other dimension of the cross section. The
Brazilian design of concrete structures standard code (NBR 6118:2014) has some procedures related
to the shear-walls analysis. Although the NBR 6118 considers it as a surface structure, this code
permits its representation by a linear element. This structural model simplification has advantages, but
nowadays, considering the wide access to computational softwares for structural analysis, it is
important to evaluate the shear-wall behavior and internal forces with more complex models. This
paper analyses several mathematical models with increasing degree of complexity (hierarchical
modeling) to simulate usual geometries of shear-walls such as rectangular, U, lipped-U and E sections,
evaluating their behavior by a Finite Elements code. The results were compared to those obtained from
the evaluation of a model considered more complex called the “comprehensive mathematical model”.
In addition, the main theoretical concepts of the hierarchical modelling are discussed.