Abstract:
With the advancement of construction technology, the focus has shifted from building a structure
that can withstand specific stress to building structures by utilizing the materials to their maximum
load capacity. This shifting of focus has made it possible to build lighter structures by eliminating
and improving old materials’ drawbacks. Concrete filled steel tubular columns are the results of
the advancement in construction technology. Their stiffness makes them suitable for earthquake
resistant structures, and the steel encasement helps to get rid of the need for formwork, which is
vital in saving money and speed of construction. Nowadays, we see rapid growth in the
construction sector of Ethiopia. Many industrial zones are being constructed all over the country.
Most of these industrial zones use steel-concrete composite materials because of the ease and
speed of construction. Furthermore, a lot of halls and churches are using composite construction.
Therefore this would be a great time to look at and research composite materials.
In this research, three types of rectangular concrete-filled steel tubular columns subjected to
different biaxial eccentricity values are studied. The parameters investigated are; height and area
of concrete of columns, yield strength of steel, steel thickness, and eccentric distance. A total of 72
different column specimen combinations are studied using the Finite Element Analysis software
ABAQUS.
A total of 150 graphs showing the load versus deformation property of individual columns, along
with graphs that compare different load versus deformation values, are presented in this research.
The deformation values which mark the columns’ elastic limit range from 2mm-4mm and that of
concentrated load varies from 3000KN – 9000KN.
The results obtained show that steel yield strength, concrete area, and thickness of steel are
directly proportional to the strength of RCFST columns and height of columns is inversely
proportional to their strength. It is also found out that the performance of RCFST columns
decreases the further the load moves away from the center of the columns,
