Title: Concrete In Transportation: Desired Performance And Specifications
Author(s): Bryant Mather
Publication: Symposium Paper
Appears on pages(s): 209-218
This lecture is about concrete - specifically, hydraulic-cement concrete. If one starts with the dry powder that is hydraulic cement - usually the particular class of hydraulic cement known as portland cement - and adds water, what results, depending on the amount of water added, is cement paste or grout. Grout can be poured like gravy. If fine aggregate is added, the result is mortar or sanded grout. If both fine aggregate and coarse aggregate are added, the result is concrete. As the Supreme Court of Pennsylvania once wrote in a decision dealing with cement-manufacturing plants, "cement is to concrete as flour is to fruitcake." My first point is, to get proper concrete, get the terminology right. There is no such thing as a cement mixer. And sand is not a synonym for fine aggregate; sand is a class of fine aggregate produced by nature rather than by rock crushers and grinding mills.