Shrinkage Behavior Of Steel Fiber Reinforced Concrete On Sandwich Layer Concrete
ABSTRACT: Shrinkage of
concrete causes a serious problem in concrete. If concrete is restrained from
shrinking, tensile stresses develop and it may exceed the tensile strength of
concrete which causes the concrete cracks. One possible method to control or
reduce the adverse effects of cracking due to shrinkage in concrete structures
is the addition of fiber in the concrete. Steel fiber can improve structural
strength, ductility, reduce crack widths and control the crack. In sandwich
layer where its material comprises of steel fiber reinforced concrete and some
other by plain concrete. The shrinkage behavior has been considerably different
compared to fiber reinforced concrete and plain concrete. Therefore this study
investigates the behavioral of shrinkage on the steel fiber reinforced concrete
on sandwich layer concept. The test specimens were made by steel fiber dosages
of 10kg/m3, 30kg/m3, 50kg/m3, 80kg/m3 and 100kg/m3 and some others for sandwich
layer specimen with similar fiber dosages combined with plain concrete. The
specimen form was cylinder 5 cm in diameter and 27 cm in high for drying
shrinkage test. All samples were placed in open air on ambient temperature
environment. The shrinkage was recorded on 1 day to 56 days. The shrinkage
prediction for three year or 1000 days was also calculated. Both recorded and
predicted shrinkage were then compared.. The test result showed that plain
concrete experienced the highest drying shrinkage and the addition of steel
fiber reduced the drying shrinkage that occurred at concrete. The greater
amount of fiber contained in the concrete, the lower occurrence of drying
shrinkage. The shrinkage on sandwich samples recorded moderate compared to
plain concrete, however this shrinkage is higher compared to samples of fully
fiber reinforced concrete at the same fiber dosage. The three group of samples;
steel fiber reinforced concrete, sandwich concrete and plain concrete showed
the same trend of shrinkage curves following the time of hydration. The
presence of steel fiber in concrete can effectively hinder drying shrinkage and
affected the crack that can reduce and control the shrinkage of concrete.
Keyword: Shrinkage behavior,
shrinkage prediction, SFRC, sandwich concrete, plain concrete, steel fiber
Author: Jibril, Ramadhan Al
Mahdi
Journal Code: jptsipilgg140019
