Aggregate Map

Selecting diamond blades for cutting concrete is made easier and more accurate when the saw operator understands the type of aggregate used in the concrete. Basically, the harder the aggregate material used, the softer the diamond saw blade bond or diamond core bit bond has to be. The bond is the hardened mixture of metal powder and diamonds that make up the segment on the blade or bit.

The colors in the aggregate map represent the hardness of the aggregate itself, and not the bond hardness of the blade or bit need to cut. So, for concrete made with very hard aggregate like quartz, the saw operator needs to select a diamond blade with a soft bond. For soft and abrasive aggregate like sandstone, the operator should select a blade with a very hard bond.

In addition, to the aggregate hardness, the heaviness type and amount of reinforcement used in the concrete will affect its overall hardness. A single mat of wire mesh will not materially affect the hardness of concrete. Multiple mats of wire mesh together with #4 - ½" rebar would count as moderately hard. Heavy reinforcement like #4 - ½" rebar, #5 - ⅝" rebar and multiple mats of wire mesh would be considered extremely hard.