A Study on Superplasticized Concrete Containing Blast Furnace Slag

Recently, the deterioration of concrete due to alkali-aggregate reaction or salt attack has become a serious matter. In order to improve the durability of concrete, it has been recommended that blast furnace slag be incorporated into concrete. On the other hand, it can be expected that the use of superplasticizer is effective to improve the workability of this type of concrete. This study was conducted for the purpose of establishing appropriate mix designs for superplasticized concrete incorporating blast furnace slag, as well as gainning an understanding of properties of fresh and hardened concretes. A superplasticizer and two types of high range water reducing agent (AE type) were used in this study. The slag contents were 0, 50 and 70%, respectively. The effects of these factors were measured by slump test, rheological test, segregation test, strength test, etc. The results showed that the flowability of cement paste increased with an increase in slag content, at a constant dosage of admixture. This effect of slag was influenced by the type and addition method of admixture. Also, the slump loss of superplasticized concrete increased with an increase in slag.