전기로 산화슬래그 혼입 고강도 콘크리트의 미세구조 및 자기센싱 특성 평가

Evaluating Microstructure and Self-Sensing Properties of High-Strength Concrete with Electric-Arc-Furnace Oxidizing Slag

This study analyzes the microstructure and strength properties of high-strength concrete containing electric-arc-furnace oxidizing slag (ES). Thus, three different water-to-binder ratios and four different ES-replacement ratios were considered while evaluating the hydration products of the specimens, their porosity, pore-size distribution, and compressive and splitting tensile strengths, depending on the curing age. According to the x-ray diffraction (XRD) patterns, the ES specimens of both portlandite and hatrurite exhibited higher peak intensities than those of the plain specimen (High-strength concrete, i.e., HSC). Further, from the results of the mercury intrusion porosimetry (MIP) test, it was observed that the cumulative pore volume of the ES specimens was higher than that of the HSC. Also, the porosity of the ES specimen, whose ES-replacement ratio was 20%, was approximately 37.9% higher than that of the HSC. The compressive strength and splitting tensile strength of the ES specimens significantly decreased when the ES-replacement ratio was 20%, while the best self-sensing properties were exhibited. From all the experiments, it was observed that an ES-replacement ratio of 15% exhibited similar microstructure and strength properties to those of the HSC.