| 摘要 |
PURPOSE:To enable formation of a hydraulic cement, good in operability and capable of exhibiting excellent strength of short and long ages and having cracking resistance, by adding a hydration expanding material and hydroxycarboxylic acid (salt) to calcium aluminate. CONSTITUTION:A hydraulic cement formed by adding a hydroxycarboxylic acid or salt thereof in an amount of 0.01-5wt.% based on outer percentage to a blend of 80-99wt.% calcium aluminate with 1-20wt.% hydration expanding material. CaO based, ettringite based, MgO based materials, etc., are cited as the moisture expanding material. Citric acid, tartaric acid, gluconic acid or potassium or sodium salt thereof, etc., are cited as the hydroxycarboxylic acid (salt). |
