In the case of concrete pavement, repairs and maintenance costs stay low because the material is sturdy. However, the rigid nature of concrete also means it is more responsive to vehicle stresses, hence cracking. Contractors play smart by applying joints in concrete structures to shift stresses.
What are Joints?
When solids heat up, they expand. When solids cool down, they contract. Concrete behaves the same way — too much expansion and contracting causes pavement to crack. The pavement is either poured in sections, joined in sections like Lego slabs, or cut into sections to allow expansion to mitigate the stress. Where the sections join, are called the joints, and the gap between is a reservoir.
Why Joints Need Sealing?
Joint sealing is a process that fills the reservoirs with flexible fillers. Poured sealed joints are smoothed out until they appear flat and repair-free. The other type is compression seals that are installed without any need for heating, mixing, or sealing. In addition to protection from water damage, joints mitigate stresses on concrete pavements, extending their durability.
At Sweeney’s Pavement Maintenance, we have some clever tips and techniques for the perfect joint sealing in concrete pavement. Best to focus on these if you are new to concrete.
- The Magnitude of the Joint – Depending on the type of reservoir, you may apply store brought joint sealer if it’s your concrete driveway. If it’s a highway, then you need professional contracting that may involve saw cutting, reservoir specs, and joint sealing.
- Always Think of the Weather – Hot pour sealants have to be heated and prepared at temperatures of 350 – 400°F, so summers are the ideal season for sealing projects or repairs. Temperatures in the winters in Dodge City can go below freezing, so winter joint sealing is best achieved with silicon sealers but beware, these take far longer to cure and may require a primer. Silicon sealers have the widest temperature range for the application. In moist weather, a general wipe down of the reservoir helps in better adhesion of the sealant.
- Be Precise on Measurements – With compression seals, 20 – 50% compression is suitable. If a compression seal is undersized, it may contract with the onset of winter, something you would not want in sub-zero temperatures. The gaps can expose the joints to damage by snow and moisture.
- Choose the Right Material – The suitable sealant should bear the deformation of the concrete as the temperature changes. Sealants are usually polymer (PVC), neoprene, or silicon-based. The sealant does not harden like concrete but provides an elastic and adhesive seal to keep water from flowing into the joint and keep from pavement failure from stress.
- Application and Supports – Silicon Sealants are easy to dispense in pre-packed containers. Polymer-based fillers are best applied by an applicator wand directly fed from the heated boiler. Always respect the cure times before allowing traffic. Backer rods are a nifty piece of support for filling varying widths of expansion joints. They are cylindrical foam tubes available in different diameters. The rods are pushed into the reservoir, and the sealant is poured over and leveled.
- Plan Maintenance – Concrete joint sealants also have a shelf life, after which they require resealing and repairs. Inexperienced or slacking contractors usually neglect this step.
Are you feeling more knowledgeable about concrete basics? Have a project you think Sweeney’s Pavement Maintenance, LLC can help you out on? Drop by our website for a free quote! We provide joint filling and saw cutting for concrete pavement all across Kansas. You can call up for projects in Dodge City, and we would be happy to serve you!