الفهرس 
الغلافيوجد فقط 14 صفحة متاحة للعرض العام
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المستخلص
Ordinary Portland cement is the main binder material in the manufacture of
concrete, however, the production of OPC is responsible for carbon hydroxide
emission and consumes a significant amount of natural resources and energy,
therefore, the use of ground granulated blast furnace slag (GGBS) as an alternative
binder material in production of environmentally friendly concrete has emerged as
an innovation solution to the pollution problem.
The experimental program composed of two phases: Phase one contains five
mix designs that were carried out to choose two suitable mix designs for using in
columns and 30 cubes ~ere cast. For each mixture, slump test and compressive
strength at 7 and 28 days were tested. Then for two mix designs that were chosen
for use in columns, flexural strength at 28 days, splitting tensile at 28 days, and
modulus of elasticity at 28 days were tested.
Phase two studies the behavior and the strength of twelve geopolymer
concrete columns under load eccentricities which were poured of the two chosen
suitable mix design from the last phase. All specimens of the experimental
program and columns were tested in the laboratories of the Housing and Building
National Research Center. The primary variables of the test series were concrete
compressive strength, longitudinal reinforcement ratio, and load eccentricity. The
test results included the crack patterns of columns, load-deflection relationship,
strain in stirrups, strain in the right bar at tension side, concrete strain at the tension
side and ductility, stiffness, and the load capacity of the columns.
Finally, the test failure loads were compared with the values calculated by
the methods currently available for Ordinary Portland Cement (OPC) concrete.
Egyptian Code 203 and the American Concrete Institute Building Code ACI 318
were used to calculate the strength of geopolymer concrete columns. Very good
correlation between experimental and the value calculated using ECP 203 was
found in which the average ratio of the experimental to the predicted axial force
(Pexp/Ppred) was 1.06 with a standard deviation of 0.077. Excellent correlation
between experimental and the value calculated using ACI 318 was found in which
the average ratio of the experimental to the predicted axial force (Pexp/Ppred) was
1.03 with a standard deviation of 0.067.