Physical and chemical properties of pre-regulated American cements

The characteristics of pre-regulated American cements differ fundamentally from those manufactured afterwards, both in terms of physical and chemical properties and with regard to cement consistency. This paper presents an overview of cementitious products available in America from 1875 to 1909. Historical testing data is compared to that expected of modern materials. The data presented show that a lack of consistency and a less rigorous manufacturing processes resulted in an original product much inferior to modern expectations regarding the compressive capacity of concrete and that this was true for both natural and Portland cements.