Admixtures – Plasticizers, super-plasticizers, accelerators, dispersants, and water-reducing agents are
some of the chemicals added to cement. These additives are sometimes used to increase the workability of a cement mixture still in “wet” form.
Aggregate – Sand, gravel, or crushed stone (rock) is used as an ingredient for concrete. Volcanic ash was used by the Romans when they began building their structures.
Binder – natural or synthetic cement.
Cement – Also known as hydraulic lime, was developed in 1756 by John Smeaton. In 1824, Joseph Aspdin and Isaac Charles Johnson took out a patent on a synthetic blend of limestone and clay. They called it Portland cement. Portland cement is made by mixing calcareous (consisting mostly of calcium carbonate) material such as limestone with silica-, alumina-, and iron oxide-containing materials. These substances are then burned until they are fused together, and the resulting admixture, or clinker, is ground to form Portland cement.
Concrete Grade – Cement, water, and aggregate are the three primary ingredients in concrete. The cement and water hold the aggregate together so the less aggregate present the stronger the concrete. The grade of concrete is measured in pounds per square inch (psi). The higher the grade the more weight it can handle. In general, 3000 psi is used for driveways.
Contraction Joints – They are shallow cuts or grooves in the concrete so that when it hardens it has a better chance to crack along the joints.
Curing or Setting – Concrete doesn’t dry. Through a chemical process, it sets or cures known as hydration. During this process water molecules combine with the concrete that form tiny crystals which interlock with each other and the aggregate. This is what gives concrete its strength.
Expansion Joints – They are usually placed 16 feet apart on large areas of concrete, but at Sudlow Concrete, we try to stay 14 feet apart for good measure. These joints span the width and thickness of the concrete. This helps give it growing room in hotter temperatures.
Fibers or Fiber-mesh – fibers made of stainless steel, glass, or carbon is added to the concrete for added support and strength to support weight on the concrete or structure. These fibers can be short, in a strand, sheet, non-woven fabric or woven fabric form.
Pozzolana – a siliceous and aluminous material often derived from volcanic ash. This reacts chemically with limestone and water that creates the basis for cement.
