Introduction:
We spend a lot of money on the concrete around our homes. Whether it is a new driveway, concrete pool deck, or the walkways around our home we expect them to last a long time. When your concrete was poured, the finisher troweled in control joints into the slab. The only intent of control joints is to control the pattern of cracking on your slabs. And trust us, your concrete will eventually crack. At TruLift Concrete Repair, we specialize in repairing and maintaining concrete. In this blog post we will discuss the ways that we can increase the lifespan and durability of your concrete.
Why Does Concrete Crack:
Concrete has a great deal of compressive strength, but not much tensile strength. In simple terms this means that you can put a great deal of pressure on the concrete and it will not smash or crush. However, it lacks tensile strength. This means that if the sub-base is not sufficient, and the concrete is not bearing evening, it can snap and a crack will appear. Even steel rebar cannot truly stop concrete from cracking. It merely holds it together after it cracks. Because of this concrete finishers trowel in control joints to make each section usually no bigger than ten by ten feet. The hope is that when the concrete does crack that is cracks in the joint, and not across the surface of the slab.
What Happens After Joints Crack:
Your control joints have done their job, and they have cracked. Now what? We know that erosion formed the Grand Canyon, and on a much smaller scale we will start to see a “mini Grand Canyon” under your slab. As rain water flows down your driveway, it now has a perfect way to drain between the slabs. This flow of water does two things. It weakens the soils under your slab, and eventually begins to erode the soil away. Over time voids will develop under the slabs, and we will no longer have a stable base under a portion of the slab. As vehicles drive across the slabs, it puts force downward on areas with voids. We know that the lack of tensile strength in the concrete will eventually cause that slab to break.
How Do We Limit The Damage:
In this article we won’t talk about the best practices for pouring concrete. If we are being honest, most concrete contractors do a very poor job properly preparing the slabs before pouring them. Rather, we will discuss what we can do after the fact to limit problems in the future. Our most effective means to extend the life of your concrete is to seal the joints properly. This can be done before the joints crack, or even after the joints have cracks. Commonly DIY’ers will pick up some self leveling polyurethane from the local big box store, and start dumping in your joints. Unfortunately, this is all too common on YouTube channels where creators are showing the easy way to do it. These sealants are rarely installed properly, are not UV stable, and just don’t look good. At TruLift we use a DOT rated silicone concrete joint sealant. We never use self leveling products because of their ineffectiveness. We apply the sealant, hand tool it with spatulas to ensure a proper bond, and then top coat it with colored polymeric sand to further protect it.
Conclusion:
We now know that control joints are meant to crack, but when they do, we begin to experience some major problems. These problems can lead to cracking in the slab, and eventually uneven concrete that poses significant safety risks. Our control joint sealing and crack repair services can greatly increase the lifespan of your concrete, and we would be happy to show you how. TruLift Concrete Repair is here for you. Contact us today for a free estimate. Visit our website at www.truliftconcrete.com or give us a call at (803) 200-2296. Connect with us on social media @truliftconcrete on Facebook, Instagram, and YouTube to stay updated on our projects and learn more about our many solutions we have to offer.
