Title: A Historical Review of the Development of Chemical and Mineral Admixtures for Use in Stucco Plaster and Terrazzo Floor
Author(s): M. Collepardi
Publication: Symposium Paper
Appears on pages(s): 673-694
Keywords: Admixtures; gypsum; lime; stucco; superplasticizers; terrazzo
When the historical buildings of the Republic of Venice were erected all the construction materials and the corresponding techniques were always carefully selected. Even at that time architects were aware of the importance of the durability of buildings in a very hostile environment such as that existing in Venice characterized by permanent humid air and capillary rise of salty water from the foundations. In particular cementitious materials were adopted in agreement with the empirical rules of the Romans’ experience and adapted for the particular Venetian environment. The present paper examines two specific cementitious materials which became very popular throughout the world: the stucco plaster and the terrazzo concrete. At the time of the Republic of Venice, chemical admixtures were not available. Therefore, masonry artisans and architects developed a special know-how to manufacture durable materials. This was based on the use of mineral admixtures and natural substances, the invention of innovative binders and the development of special application techniques. After the advent of portland cement and especially of chemical admixtures, modem stucco plaster and terrazzo concrete can be produced with different (not necessarily better) properties and at higher rates of productivity. The present paper examines the microstructural aspect, the composition, the performance, and the manufacturing process of the original and modem materials.