Saw cuts are an integral part of a high quality piece of concrete. They may seem to have no practical or aesthetic purpose, but rest assured, they do indeed have a purpose! The purpose of saw cuts is to help control cracking in concrete. Cracking can occur because of shrinkage in the concrete.
It is very important that the saw cuts be made after the concrete has reached sufficient strength. They also need to be made before any cracking begins internally. You should choose a concrete company that is trained in all aspects of concrete and competent in choosing the correct timing for making the saw cuts.
Yes, the weather certainly does affect the timing of making the saw cuts. In the heat of summer, the saw cuts may be made as soon as four hours after having the concrete poured. When the weather is cooler, the sawing may not start for up to twelve hours after the concrete is poured. A competent concrete team will know the best time to decide when the cement is ready to make trial cuts to test the concrete. When raveling stops during the trial saw cuts, it is time to begin the saw cutting in your concrete project.
If the saw cuts in your sidewalk, driveway or garage pad are made too early, it can be the cause of what is called raveling. Raveling is caused when saw cuts are made prematurely and happens when the saw blade pulls the aggregate out of position. Instead of a smooth, even cut, there is a weakened, rough edge where the saw cut was made. Your concrete team will prefer to not have this happen, as it also causes extra wear and tear on their concrete saw blades. There are early entry, dry cut saws that can be used soon after the finish work.
On the other hand, if saw cuts are made too late, it can cause uncontrolled cracking of the cement. It is of utmost importance to choose a group of professionals who know and understand the ins and outs of concrete curing and the timing of making the saw cuts.
Your concrete team will know how important it is to choose where the saw cuts need to be made. Usually the saw cuts begin on or at the center of column lines. If the cement used for your project is high shrinkage, the spacing between cuts may be lessened. The saw cuts should be made continually. There are other factors used to determine exactly where to make the saw cuts.
Usually, saw cuts are made about ten to eighteen feet apart. They should begin at the center of the column lines. Joints should be spaced twenty-four to thirty-six times the slab thickness, although this can vary. Ten to eighteen feet is the normal spacing between joints. This can differ according to the amount of reinforcement there is in the concrete project.
The joints should be cut twenty-five per cent of the depth of your slab. Therefore, a four inch slab should have joints which are one inch deep. Groover tools are the tools used to cut joints in the fresh concrete. In interior projects, the joints should be placed where they will not be obvious, such as under carpet or under a wall. The joint pattern should be planned ahead by a knowledgeable person.
