Despite the heavy-duty tools required, cutting concrete is delicate business. Artfully curated from experience, there are many factors to consider when cutting concrete. Understanding your site and the role your external factors can play in cutting concrete is crucial. With an array of aspects to consider when determining the depth of your cut, it’s not as simple as it looks. From weather conditions to using the correct concrete saw, ensuring you have in-depth knowledge before starting is crucial.
Methods of Cutting Concrete
Wet cutting
When concrete is cut, silica dust can be produced. This dust can be detrimental to your health causing a large amount of health issues, specifically to your lungs and respiratory system. Cutting wet can assist in the control of the dust and reduce the dust concentration by at least 85%. Wet cutting will also improve the performance and life of your blade.
Dry Cutting
Usually executed when there is no water source available or when the job site needs to stay dry, this style of cutting will produce large amounts of fine silica dust so the relevant PPE equipment is a must, also dust extraction vacuums may be required. Ensure you have a blade that is designed for dry cutting. Note, concrete diamond blades will wear quicker when dry cutting.
Cutting Concrete Depth
Aiming to cut expansion cuts to a depth of one quarter to one-third of the concrete thickness is a good rule of thumb to follow when cutting concrete. Even professionals can experience cracks in the concrete, but expertise minimises this possibility. Seek structural engineer knowledge for sufficient advice to avoid hick-ups.
Concrete shrinks as it cures, the rate of shrinkage is determined by a lot of factors; weather, humidity, air temperature, wind, the mix (cement to water ratio) or slump rating and other factors. Cutting control joints/expansion joints as early as you can helps avoid the visible cracking that occurs as concrete cures.
Cut when the concrete has obtained enough strength but before internal cracking begins. Cut with predetermined spacing, made on or at the centre of the column lines. Forming square patterns with continuous cuts is key in ensuring your slab stays crack-free. Make some trial cuts, if possible, to assess what situation your slab is in.
Timing is important and varies from day to day. Cutting too early can produce a messy look but cutting too late can cause further cracking. Cutting usually occurs between six to 18 hours. If you’re cutting in cooler weather, 12 hours should suffice. Hot weather calls for a quicker cut; usually around four hours.
Cutting too deep can cause aggregated interlocking to be disturbed making it insufficient to carry heavy loads. Cutting too shallow can cause random cracks.
Tools Required
Tools are the most important part of your job. Ensuring you have quality saws before beginning a project is crucial. The job required will determine your choice of tools.
Meiwa’s range of concrete cutting saws is designed to streamline operations. Featuring accurate and easy to operate models, offering different weight categories and blade dimensions, there is a saw for every site. Get your job done right with a durable, comfortable, safe and reliable concrete saw.
More questions? Contact us today for more information on your next concrete cutting project!