The mechanism of the hydration in the system C3S-pozzolana

✍ Scribed by K. Ogawa; H. Uchikawa; K. Takemoto; I. Yasui

• Publisher: Elsevier Science
• Year: 1980
• Tongue: English
• Weight: 956 KB
• Volume: 10
• Category: Article
• ISSN: 0008-8846
• DOI: 10.1016/0008-8846(80)90032-0

✦ Synopsis

A mixture of five kinds of Japanese pozzolanas and synthesized pure C3S were hydrated. The hydration mechanism in the system C3S-pozzolana was investigated. The hydration of C3S was accelerated by the addition of pozzolanas. The reasons for the acceleration increase of the precipitation sites of hydrates and the increase of the dissolution speed of C3S caused by the depression of Ca 2+ ionic concentration in the liquid phase was due to the addition of pozzolanas. The reaction between pozzolana and formed Ca(OH) 2 is pronounced after 1 to 3 days. Zonal hydrates existing between C3S and pozzolana grains have Ca ionic concentration gradient from C3S to pozzolana. It was often observed that in intact pozzolana grains which had no precipitated hydrates, there was clearance between pozzolanas and hydrates, and cast of trace. That tendency was pronounced in pozzolanas which had substantial alkalies. The mechanism of the hydration in the system C3S-pozzolana was considered from those results.