الفهرس 
LITERATURE REVIEW AND BASIC VARIABLESOnly 14 pages are availabe for public view
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Abstract
Reinforced concrete (RC) columns are considered the most important structural element in the skeleton type structures. The design of RC columns
has been developed in the last third of 20
th
century through a large number
of experimental and theoretical researches all over the world. Previous researchers studied the general behavior of RC columns under various loading types, different reinforcement details, several concrete grades exposure to severe environmental conditions and verifications of code provisions. The objective of this research is to establish a mathematical formula
to predict the ultimate load capacity for axially loaded short columns taking
into consideration the variation of lateral steel reinforcement represents the confinement effect for both square and circular RC columns. The effect of concrete compressive strength f
cu,
, the
effect of concrete cross section shape
( square – circular – rectangular ) and the concrete cross section area were
studied as well.
For this purpose, a total number of 12 specimens were prepared and
tested experimentally under axial load to study the parameters that correlated
to confinement. Tested columns were divided into 2 main groups in which
one of them contains 9 specimens with a concrete compressive strength
equal to 25 MPa and varying in transverse steel volumetric ratio, concrete
cross section shape in addition to cross section area. The second group
contains 3 specimens with a concrete compressive strength equal to 40 MPa.
to study the effect of concrete compressive strength.
The results of all tested specimens (ultimate loads-strainsdeformations…etc)
were
recorded
and
discussed.
Different
gains
of
strength,
stiffness
and ductility were recognized. Mathematical formulas to correlate
the axial capacity for both square and circular specimens were determined as
well. the longitudinal steel for all specimens was kept constant with a ratio
of 1.28% of the concrete cross section area.
To verify the experimental results, the tested specimens were analyzed
numerically using a non linear finite element program and the obtained
results were compared to those obtained experimentally. the ultimate loads,
deformations and strains were also recorded and comparedAlso, a parametric study was carried out using the non linear finite
element program mentioned above. The parameters studied were the
concrete compressive strength and transverse steel volumetric ratio for both
square and circular columns and the concrete cross section area of square
columns.
For all of the two phases of the research ( experimental work,
numerical analysis) the equations correlating axial capacity of the column to
transverse steel volumetric ratio were obtained. For the parametric study, the
equations correlating the axial capacity of the column to the transverse steel
volumetric ratio and concrete compressive strength were obtained for both
square and circular columns. The equation correlating the axial capacity of
the square columns to the concrete cross section area of the columns was
obtained as well.
The overall research conclusions were listed at the end of the research
in addition to the future research suggestions.
Keywords
Axial loads; Confinement; Transverse (Tie) steel; Compressive concrete
strength; Volumetric ratio; Short columns; Cross sectional area: Numerical
study, Parametric study, Mathematical formula