Abstract:Steel slag is the second largest waste product in metallurgical industry. Making full use ofwaste steel slag to partially replace sand and gravel as a new type of geotechnical filler aligns with thestrategies of "green economy" and "sustainable development". Steel slag differs from sand and graveldue to its complex chemical composition and aging mechanical properties. Resonant column tests wereused to study the dynamic characteristics of steel slag considering the influence of hydration period. Itanalyzed the variation patterns of dynamic shear modulus and damping ratio. The dynamic characteristicsof steel slag considering time effects were described by using the Hardin-Drnevich hyperbolic model,and the Boltzman function was employed to describe the relationship between the maximum dynamicshear modulus and the hydration period, providing the range of maximum damping ratio. Comparing these dynamic characteristics with traditional sand, the dynamic shear modulus of steel slag beforehydration was slightly higher than that of traditional fine sand, and the maximum dynamic shearmodulus of standard sand could be reached after 90 days of hydration. This indicates that steel slag canbe used as a filler to replace sand in engineering applications. Finally, the microstructure of steel slagat different hydration periods was analyzed by scanning electron microscope, revealing that the formationof hydration product Aft occurred in later stages compared to other hydration products. The gelstructure composed of Aft and C-S-H was the main factor affecting the aging characteristics of steelslag dynamic properties.
