Exploration Testing on High-Performance Cement-Based Materials Using Granulated Blast Furnace Slag as Fine Aggregates

This study investigates the feasibility of using granulated blast furnace slag (GBFS) as fine aggregates for high-performance cement-based (HPCB) materials. The mixture ratio of HPCB materials using GBFS as fine aggregates is calculated based on the dense packing theory of aggregates and the minimum water requirement. A series of cement-based material mixes are prepared with three water binder ratios (0.16, 0.18, and 0.2) and three GBFS replacement ratios (0%, 50%, and 100%). Various properties of the cement-based materials, such as the compressive strength, flexural strength, splitting tensile strength, and elastic modulus, are studied. The research on the selected HPCB material compositions using scanning electronic microscopy (SEM), hardened concrete pore structure determination (HCPD), and mercury intrusion porosimetry (MIP) enables a further understanding of the relationship between the mechanical properties and microstructures. The test results show that it is feasible to produce HPCB materials using GBFS as fine aggregates. Despite its large crushing value index and irregular particle shape, GBFS has hydraulic properties that can make up for these disadvantages. GBFS and mixed fine aggregate cement-based materials with good properties can be prepared with a reasonable mix design. The strength of such cement-based materials is consistent with that of ordinary quartz sand (QS) fine aggregate cement-based materials. The compressive, flexural, and splitting tensile strengths of GBFS and mixed fine aggregate cement-based materials may be higher than those of ordinary QS fine aggregate HPCB materials. The relationship between the compressive strength and porosity is in agreement with the formulas proposed by Powers, Ryshkevitch, Schiller, and Hasselman.