TY - JOUR
T1 - Physical and chemical properties of concrete using GGBFS-KR slag-gypsum binder
AU - Cho, Bongsuk
AU - Choi, Hyeonggil
N1 - Publisher Copyright:
© 2016
PY - 2016/10/1
Y1 - 2016/10/1
N2 - The Kambara reactor (KR) slag, which is a byproduct generated in the preliminary treatment process of molten iron by a KR mechanical stirring process, is composed of Ca(OH)2, CaCO3 and 2CaO·SiO2. It was confirmed that the alkali stimulus of Ca(OH)2 contained in the KR slag could cause a cement-free binder to harden. However, the strength performance of a GGBFS-based cement-free binder mixed with only the KR slag was very low. The gypsum (CaSO4) is additionally used in order to enhance the strength performance of the GGBFS-KR slag binder. The result showed that the 28-day compressive strength of the GGBFS-KR slag-gypsum binder (GKGB) concrete was similar to that of slag cement. On the other hand, compared to those of slag cement, the drying shrinkage was shown to be 121.8–129.0%, and the cumulate porosity was shown to be 190–208%. These results imply that ettringite, which is a main hydrate of GKGB, is thick and provides the structural stability by forming a frame structure. However, the thicker ettringite, the more pores may be created. In other words, high amounts of ettringite form a porous structure, which has many micro pores so that the porosity and absorption become higher, leading to higher drying shrinkage.
AB - The Kambara reactor (KR) slag, which is a byproduct generated in the preliminary treatment process of molten iron by a KR mechanical stirring process, is composed of Ca(OH)2, CaCO3 and 2CaO·SiO2. It was confirmed that the alkali stimulus of Ca(OH)2 contained in the KR slag could cause a cement-free binder to harden. However, the strength performance of a GGBFS-based cement-free binder mixed with only the KR slag was very low. The gypsum (CaSO4) is additionally used in order to enhance the strength performance of the GGBFS-KR slag binder. The result showed that the 28-day compressive strength of the GGBFS-KR slag-gypsum binder (GKGB) concrete was similar to that of slag cement. On the other hand, compared to those of slag cement, the drying shrinkage was shown to be 121.8–129.0%, and the cumulate porosity was shown to be 190–208%. These results imply that ettringite, which is a main hydrate of GKGB, is thick and provides the structural stability by forming a frame structure. However, the thicker ettringite, the more pores may be created. In other words, high amounts of ettringite form a porous structure, which has many micro pores so that the porosity and absorption become higher, leading to higher drying shrinkage.
KW - Cement-free binder
KW - Ettringite
KW - GGBFS
KW - Gypsum
KW - Iron & steel making process
KW - KR slag
KW - Porosity
KW - Shrinkage
KW - Strength
UR - http://www.scopus.com/inward/record.url?scp=84978886174&partnerID=8YFLogxK
U2 - 10.1016/j.conbuildmat.2016.07.023
DO - 10.1016/j.conbuildmat.2016.07.023
M3 - Article
AN - SCOPUS:84978886174
SN - 0950-0618
VL - 123
SP - 436
EP - 443
JO - Construction and Building Materials
JF - Construction and Building Materials
ER -