Lecture
This lecture delves into the hydration process of calcium silicates, focusing on C3S and C₂S. It covers the formation of calcium hydroxide, portlandite, and calcium silicate hydrate (C-S-H), which constitutes a significant portion of the hydrated paste. The lecture explores the structure of C-S-H, including its variable calcium to silicate ratio and ways to modify it. It discusses the substitution of silicon by aluminum in C-S-H and the experimental evidence supporting its structure. The lecture also presents different models describing the atomic, meso, and microstructure of C-S-H, shedding light on its complex nature in cementitious materials.