Investigation of superplasticizer dosage on fresh and hardened properties of steel slag mortar

• Main Authors: Ho, Chia Min, Doh, Shu Ing, Jing, GuoQing, Chin, Siew Choo, Li, XiaoFeng
• Format: Conference Proceeding
• Language: English
• Subjects: Cement constituents; Compressive strength; Dosage; Flexural strength; Mortars (material); Slag; Steel constituents; Superplasticizers; Sustainable development; Sustainable materials; Water absorption; Workability
• ISSN: 0094-243X; 1551-7616
• DOI: 10.1063/5.0112985

The high demand from concrete manufacturing and applications which sourced from non-renewable source have led to a severe environmental issue. Therefore, sustainable materials which sourced from renewable source should be explored to replace the main constituent materials-cement in concrete while promoting sustainable development. Steel slag (SS) is one of the sustainable materials used as supplementary cementitious materials in concrete. However, previous studies revealed that steel slag lead to poor workability due to its characteristics. This study aims to investigate the effect of superplasticizer (SP) dosage of 0, 0.5, 1.0 and 1.5% in SS-based mortar. The experimental tests included were the flow table test, compressive strength test, flexural strength test and water absorption characteristic in this study. The results show that the increase of SP dosage has significantly increased the workability of fresh SS-based mortar. However, with the increase of SP up to 1.5%, bleeding has occurred. The compressive strength and flexural strength of 1% dosage has shown improvement after 28-day of curing compared to the control specimen. The water absorption rate of SS-based mortar reduces gradually with the increase of SP up to 1% and increases when the dosage of SP exceeding 1%. The experimental result shows that the optimum dosage of 1% SP gives good performance in workability and yields the highest strength of 53.6MPa at 28-day.