The cuts should be made at a predetermined spacing and onlyafterthe concrete has obtained sufficient strength butbeforeinternal cracking begins.
Therefore, the timing of saw cuts is critical.
Sawing too late can result in uncontrolled cracking as the concrete contracts during curing.
The Spruce / Jacob Fox
The best way to determine whether the slab is ready is to make trial cuts to check for raveling.
Saw cutting should start as soon as the raveling stops during these trial cuts.
Some contractors delay sawing to protect their equipment and saw blade to reduce blade abrasion.
The Spruce / Jacob Fox
you’d be smart to start saw cuts on or at the center of column lines.
Joint spacing normally ranges between 12 to 18 feet depending on the amount of reinforcement the slab has.
If you are using high shrinkage concrete, you might want to decrease the cut spacing.
The Spruce / Jacob Fox
Once you’ve laid out the joints to be cut, mark them using a chalk line.
For a 6-inch-thick slab, that means cutting 1 1/2 to 2 inches deep.
Ensure that the saw cut depth meets the structural engineering specifications.
The Spruce / Jacob Fox
If the joint is too deep, aggregate interlocking will not be sufficient to transfer loads.
If the saw cut is too shallow, random cracking might occur.
Guide for Optimum Joint Performance of Concrete Pavements.Iowa State University Institute for Transportation.
Job Safety Analysis.University of North Carolina at Chapel Hill.
