Besides being ugly, broken or cracked concrete can create an unsafe surface for driving and walking. In addition, damaged concrete creates an opportunity for water to soak below the surface where it damages the base materials and further degrades the concrete surface. If you find yourself with a broken or cracked concrete driveway, refer to the information in this article to determine what type of damage you have and the recommended concrete repair strategies.
Well-functioning concrete always begin with using a proper mix design and strength specifications at initial construction. The performance also depends upon the proper installation techniques by the contractor. Sadly, there is no guarantee that your concrete driveway, patio, or walkways were designed and built correctly. This is why we see a lot of failing concrete. On top of that, even the best designed and built concrete can be damaged by exposure to excessive weight loads that it wasn’t designed for.
If you would like to have professional analysis of your concrete or driveway damage in the Jacksonville area, contact Ethos Landscapes for a consultation. We have years of experience inspecting and identifying concrete distresses and the corresponding concrete repair strategies.
Typical Performance of Concrete Pavements
When designed, constructed, and maintained properly, concrete pavements have a long service life. Most high-quality concrete pavements do not start to exhibit distresses for at least 15 years if they are used as intended. For example, if heavy vehicles repeatedly drive over a residential sidewalk, it will inevitably break because it wasn’t designed to handle that weight load.
Technically, the service life ends when the concrete breaks up into small, unstable pieces and then problems lead to the pavement not being able to support the intended loads.
The service life of pavements can be extended by prompt maintenance of problems, especially at joints and cracks to prevent water and foreign materials from entering the cracks and joints.
For those of you in the process of building a project, we urge you to hire a reputable concrete contractor that will use the proper installation techniques and concrete mix designs for your geographic region.
Let’s begin with identifying some common concrete distresses and their underlying causes.
Identify the Underlying Cause
The first step involves inspecting and identifying the underlying cause of the problem. Once identified, this underlying problem must be corrected prior to repair or replacement to avoid it happening again.
Some common underlying problems include damage to the base materials below the concrete surface, freeze and thaw cycles, foreign materials in the joints that prevent expansion and contraction, poor materials, and many more.
Professional hardscape design and construction companies are able to inspect and identify these problems. Once determined, your hardscape company can determine the concrete repair strategies best suited to fix the problem.
Common Concrete Distresses
Cracking
Corner Break
As you can probably guess, a corner break is a crack that occurs on the corner of a concrete slab. This crack will extend all the way through the entire concrete slab.
Corner breaks are usually a result of repeated traffic loads over concrete slabs where the supporting base materials have been damaged. The base layers cannot provide solid support for the concrete, so it completely cracks through.
Depending upon the severity, a full-depth repair and reconstruction of that portion of the slab and base materials are recommended.
Linear Cracking
Linear cracks are common in concrete. Just as it sounds, these are simply cracks in the concrete. Depending upon their size and width, these cracks may or may not pose a risk to the slab.
Cracking is usually caused by a combination of factors, including repeated traffic loadings, shrinkage stress, and environmental conditions. They can also be caused by poor pavement design or poor construction.
Crack sealing is most commonly the preferred repair strategy for linear cracking.
Spalling
Spalling occurs when the concrete along the edges of the slab cracks and breaks down. Eventually, the spall creates chunks of loose concrete. Unlike a corner break, a spall does not crack all the way through the slab. Instead, the crack goes diagonally through the slab.
Excessive stresses at the joints between slabs cause spalling. When rocks or other foreign items enter the joints between the slabs, they create an environment that doesn’t allow the concrete slab to expand in hot weather. This results in the concrete spalling since it is prevented from expanding.
Spalling may also be a result of weak concrete at the joints, usually a result of poor construction methods.
Partial-depth repair is typically used to repair spalling.
Shattered Slab
If a concrete slab is divided into 4 or more pieces by intersecting cracks, then it is considered a shattered slab. This is the most severe distress and should be addressed quickly to allow for the continued safe use of the pavement.
Shattered slabs are typically a result of overloading and lack of base support. Essentially, the concrete and base layers are not strong enough to support the weights being placed on them, so they severely crack.
Concrete slab replacement and base material repair is the recommended solution when shattered slabs occur.
Surface distress
Patching
An area where the original pavement was removed then replaced with a new material is considered patching. If done correctly, patching can extend the service life of concrete. However, if done incorrectly, patching can add further damage to pavements.
Working with a professional hardscape company is essential for patching concrete. Using regionally appropriate materials, as well as materials compatible with the existing concrete is essential. The goal is to install a patch that will expand and contract at similar rates to the existing concrete to prevent further cracking.
Failing patches should be removed and repaired properly.
Why should repair your broken concrete?
The goal should be to extend the life of your pavement to save money and resources. Do you want to have a costly driveway replacement because you failed to repair and maintain it properly? Most people prefer the costs savings of maintenance and repair over expensive replacement costs.
When concrete is maintained and repaired promptly, the smooth riding or walking surface is preserved, the surface can continue to be used safely, and most importantly, water is prevented from entering the underlying soil which extends the lifespan.
Typical Concrete Maintenance and Concrete Repair Strategies
Joint Care
Taking care of the joints between pavement surfaces is a relatively simple task that yields big results. All joints should free of any debris or vegetation which may impact the natural expansion of the slab. Depending upon the type of joint and maintenance required, clearing the joints can be done with pressure washers, compressed air, and hand tools.
Joint care also involves monitoring the condition of any sealants present in the expansion joints. Sealants should be pliable and elastic to the touch. A firm connection between the sealant and the joint edges of the concrete slab is required to prevent water intrusion into the base layers.
Replacement of the joint sealant is recommended if it is missing or damaged. Again, the goal is to prevent water and rocks to enter the joint which will lead to cracking and spalling.
Crack Sealing
Similar to joint sealants, crack sealants provide a barrier for water and debris to enter the crack. This type of repair, along with joint sealants, are the most common concrete repair strategies.
A simplified explanation is that crack sealing involves removing old sealant, sawing/routing the crack to a desired depth/thickness, cleaning the crack, installing a backer rod, and then new sealant installation.
Partial-Depth Repair
Partial-depth repairs are primarily used to fix spalls at joints or spalls along cracks. Since spalls don’t extend all the way through the slab, a partial depth repair can be used.
Correcting spalls can extend the life of the pavement, restore rideability, and provide a proper joint edge for sealant.
A partial-depth repair includes removing a section of the upper layers of the existing concrete surrounding the spall. Upon removal, the area is properly cleaned prior to a concrete patch and new sealant being installed.
Full-Depth Repair
Full-depth repair is required when cracks or distresses extend all the way through the slab. Corner breaks, shattered slabs, or extreme spalling are distresses which are best fixed with full-depth repairs.
Think of a full-depth repair as complete replacement of a section of concrete. This involves removing the damaged concrete, then repairing any damage to the base layers. Once the base layers are prepared, new concrete is installed with appropriate design and reinforcement as required.
Closing Thoughts
If you maintain and repair your concrete pavements, they can provide a safe, stable, and smooth surface for decades. Repair and maintenance don’t have to be expensive or difficult, but it does require an awareness of how concrete works. The first step is awareness, but the next step should be involving a professional that can provide you with guidance on materials and methods that will work in your geographic area. DIY is not a good idea if you want high quality, long-lasting surfaces.
I hope this article gives you some ideas you can ponder the next time you notice a crack in the concrete!