Concrete has the ability to move due to shrinking. This can be when it dries or is exposed to the natural elements over time. When a part of the concrete shrinks, it can result in cracking. This can be problematic because water and dirt can get into these cracks, creating problems for your concrete. Joints allow the concrete to move as needed with extreme cracking and a sealant needs to be applied to protect these joints from the weather. Here are the three types of joints that might require a concrete joint sealant.
Concrete is commonly used to keep another object in place. This might be a wall, a column, or a drain pipe. This object is not going to shrink as the concrete does as it dries. This can create problems for the concrete and for the object that it’s holding into place. For this reason, an isolation joint is commonly included in the concrete. This joint keeps the concrete from the object that it’s holding so that the shrinking concrete doesn’t affect the object.
When pouring concrete for any purpose, you usually won’t pour all of the concrete at once, In most cases, part of the concrete will be poured and shaped before the rest is applied. This is where a construction joint is included. This type of joint allows for the placement of the slab without the wet concrete moving into areas you have yet to fill. This type of joint is especially helpful if something causes a delay in the pouring of the rest of the concrete. A delay could be caused by an equipment malfunction, a shortage of materials, or bad weather. A construction joint will ensure that the already-poured concrete is stable before you pour the remainder of the slab.
Unlike isolation and construction joints, which are placed prior to the pouring of concrete, contraction joints are included after the concrete has been poured. These are basically small cracks placed into the concrete so that you can control the inevitable cracking once the concrete begins shrinking. While a slab of concrete will have to crack regardless, you want to control the amount of cracking and the size of the cracks. Contraction joints allow you to do this. Once the cracking begins, it’s called joint activation.
There are different types of joints that might be included when pouring concrete to help control the shrinking process. This allows you to control cracking, protect objects being held by the concrete, and ensuring you can pour all of the concrete safely. These are the three types of concrete joints that might be used and require a concrete joint sealant.