| Title |
Strength and Drying Shrinkage Cracking of Concrete Using Dune Sand and Fly Ash |
| Authors |
고정원(Ko, Jeong-Won) ; 유재강(Yoo, Jae-Kang) ; 이의배(Lee, Eui-Bae) ; 박상준(Park, Sang-Jun) |
| DOI |
https://doi.org/10.5659/JAIK.2020.36.10.199 |
| Keywords |
dune sand; fly ash; compressive strength; net time-to-cracking; restraint effect factor |
| Abstract |
In the Middle East, dune sand is used as fine aggregate for concrete. The purpose of the use of dune sand is the grading correction of
crushed sand. Most of the existing research on dune sand have been conducted by focusing on the workability and strength of concrete.
However, the region using dune sand as concrete aggregate generally has desert climate, and it is the worst condition in the drying shrinkage
cracking of concrete. Therefore, the investigation on drying shrinkage is needed for dune sand concrete as well as workability and strength.
In this study, the strength and drying shrinkage cracking of fly ash concrete using dune sand were evaluated. The result showed that the
maximum compressive strength and the maximum split tensile strength were shown in concrete mixture of dune sand replacement ratio 10%.
The maximum net time-to-cracking was shown in concrete mixture of dune sand replacement ratio 20% and the net time-to-cracking
decreased with the increase of dune sand replacement when dune sand replacement ratio was over 20%. For stress rate, concrete mixture of
dune sand replacement ratio 60% showed the lowest value. Also, based on the changes of aggregate volume and the net time-to-cracking, the
restraint effect factor could be calculated in this study. |