Numerical modeling of cold-formed steel-concrete columns

Resumo

The objective of this study was to perform numerical simulations through the FEM method, using
ABAQUS®, to investigate the structural behavior of Cold – formed steel - concrete columns (CFSC). The
concrete’s influence on the system's efficiency was investigated for systems with different heights between 2.50
and 3.00 meters, since most of the articles with CFSC show results for short columns up to 1 meter. The results
showed that the concrete favors the structural behavior, but this resistance’s gain is reduced as the systems become
higher due to the buckling action: In the columns with 1.5 meters, concrete contributed to a more than 100 %
increase in the strength of the columns, while for columns with 3 meters, this gain was only 28%. In columns with
2.5 meters, this gain represents 70%. Even with the loss in strength of the composite systems due to the increase
in slenderness, the encased columns with 3 meters in height presented strengths of almost 100 kN, which
corresponds to the average values requests in small buildings. In simple steel tubular columns, these values did
not reach 60kN.