Improvement of vibration resistance of slag blended cement mortar using C-S-H seeds

To assess the feasibility of using C-S–H seeds to boost the anti-mechanical vibration capabilities of concrete, this work evaluated the mechanical properties, hydration kinetics, phase assemblage of hydrates, and pore structure of Portland cement (PC) and slag cement mortars, at varying dosages of C-S–H seeds. Results reveal that the incorporation of C-S–H seeds negatively affects the vibration resistance of neat PC, while it effectively enhances the vibration resistance of slag cement. The addition of these seeds facilitates cement hydration and improves the early mechanical properties, which is evident in the shortened appearance time of the hydration exothermic peak by almost 50%. The remarkable vibration resistance observed in slag cement primarily stems from the synergistic effect between C-S–H seeds and slag. However, the premature formation of the internal microstructure in neat PC due to C-S–H seeds disrupts the stability of mutual construction between hydration products. The findings indicate that C-S–H seeds can be used in engineering to enhance concrete lifespan, reduce road repair expenses, and enhance construction efficiency.