Your Reference Guide to Concrete Repair for Common Causes of Damage
Key Takeaways:
- It’s critical to manage the lifespan of concrete by recognizing the need to repair and by applying the right repair materials at the right time
- Concrete can be damaged by normal wear and tear, physical collision events, improper design, or repeated exposure to heat and cold
- There are a variety of preventive measures and repair options for concrete
- Long-lived concrete starts with high-quality materials – it’s important to choose superior concrete for the life of the project
Maintaining an industrial project requires knowledge of the associated concrete repair materials used for polishing, grinding, and coating concrete for longevity. Like any building material, concrete is subject to gradual wear and tear. Even natural wear and normal use can lead to damaged areas in the concrete over time, and you can extend the natural lifespan of the concrete by inspecting and repairing it regularly.
What causes damage to concrete?
It’s important to identify any direct causes of damage (if there is one) and ensure that future repairs will withstand that damage in the future, or to remove the source of damage entirely.
If the damage is caused by structural overload, for example, it’s critical to make changes to ensure the surface won’t be overloaded again after repair. Luckily, most concrete damages are caused by recurring problems that can be fixed or avoided.
Damage to concrete can be caused by:
- Freeze-thaw cycles
- Erosion
- Excessive heat
- Overload and impact
- Surface defects
Freeze-thaw cycles
Due to the expanding and contracting that occurs when the moisture in concrete freezes and thaws, these cycles can cause significant damage to concrete surfaces.
Creating air voids in the concrete allows room for this fluctuation of surface area and helps prevent cracking and crumbling. Low-permeability concrete is another solution to damage caused by freeze-thaw cycles.
Erosion
Erosion or abrasion damage generally occurs due to excessive use, when the surface wears down from the friction that occurs in high-traffic areas. Such damage is typically caused by industrial equipment, vehicles, and hydraulic structures.
The most effective solution to erosion/abrasion damage is ensuring the quality of the aggregate. Making sure tough, wear-resistant aggregates are used in the concrete is the most important step in producing surfaces with high abrasion resistance.
Excessive heat
When exposed to extremely high temperatures, concrete can eventually lose some of its strength and hardness. Essentially, the excess heat causes the materials in the concrete to transform, becoming weaker and/or more pliable.
Testing the concrete under higher heat conditions and, again, choosing the best aggregate for the concrete are the best options to ensure it will hold up more effectively against excess heat and thermal cycling.
Overload and impact
Excessive weight on the concrete’s surface or an unexpected change to the structure are the most common causes of overload damage. The damage caused by an earthquake and use of concrete surfaces prior to them having reached their design strength are common examples of overload damage.
The most common form of impact damage occurs in high vehicle-traffic areas, particularly on slab joint edges. The best solutions to overload and impact are proper structural design, including the use of reinforced steel.
Surface defects
Air voids, honeycombing, streaking, and dusting are just a few types of surface defects that can occur on concrete and are created by trapped air, excess moisture, and temperature shifts, among other causes.
Ensuring the use of proper materials, cure time and hydration, air flow, and controlled temperatures can help avoid these common surface defects in concrete.
Concrete coatings can help
Adding protective coating as a preventive measure is the first, best step to avoid any of these common causes of concrete damage. In some cases, sealers and coatings can be used to repair damage as well.
You can use the term “coating” to refer to any liquid or semi-solid product you use to repair cured concrete, but the term more precisely refers to polymers that are less than 1/16th of an inch thick when applied. They include:
- Epoxy-based products
- Urethane-based products
- Acrylic-based products
- Polyurea-based products
These products have a few properties in common. They often have fast curing times, limited VOC (volatile organic compound) exposure, and improved performance compared to cement-based coatings, paints, toppings, and overlays. Each type of concrete coating product has its own benefits and use cases. There are different repair situations in which you’d want to use epoxy-based coatings, for instance, over acrylic-based.
Epoxy-based coatings
Epoxy-based coatings are a go-to option for many contractors because they have high abrasion resistance, good hardness, and a durable glossy finish. For years, epoxy has been the preferred coating type for repairing and rejuvenating commercial flooring as well as garage floors.
Urethane-based coatings
Urethane resin coatings are one of the most economical choices for large spaces and they’re also very durable, with a lifespan of up to 30 years. These coatings are antimicrobial, which protects against fungal and bacterial activity, increasing the life of the flooring before repairs and maintenance will be needed.
Urethane-based coating is thermal shock resistant, allowing it to withstand thermal cycling from hot- and cold-water exposure. This makes it a great choice for repairing floors that will be exposed to constant cleanings, such as breweries, pharmaceutical manufacturing, and food manufacturing.
Finally, urethane floor coatings have high slip resistance, making them a good choice for heavily trafficked areas and workplaces.
Acrylic-based coatings
Acrylic coatings work by forming a film over the surface of the concrete, making them safer against moisture compared to coatings that work by penetrating the surface. This feature also makes acrylic coatings stain resistant and actively protects against chipping or cracking.
This type of coating is known for being ultra-easy to prepare and apply, with minimal preparation needed to the surface. It’s a good choice for outdoor projects such as decks and driveways because of its 100% ultraviolet resistance.
Some contractors prefer the aesthetic look of an acrylic-based coating as the satin-like and matte appearance give it a more natural look.
Polyurea-based coatings
Polyaspartics are the most common polyurea-based coating on the market, and one of the newest as well. Because they set so quickly, these coatings are extra-appealing in repair projects with fast turnaround times.
The biggest benefit of a polyaspartic coating is that you can apply it in a single coat at full thickness, removing the need to layer multiple coatings.
These coatings are also better at resisting abrasions and impact than epoxy-type coatings, and they can be applied at any temperature. They bond well and have high stability under ultraviolet light, which adds to the durability factor.
Polyaspartic coatings are the repair coating of choice for garage floors and driveways, auto showrooms, and even warehouses due to their high capacity to resist wear and tear.
Concrete repair
If the damage has already been done, there are steps to take to ensure the best repair options for your concrete:
- Determine the cause
- Evaluate the damage
- Choose the best repair method for the job
- Prep the damaged concrete
- Apply and properly cure the repair
Thin repairs are generally limited to up to two inches deep and do not involve the existing reinforced steel in the concrete structure. In addition to using sealers and coating, thin repairs include surface grinding and various mortars, such as cement, dry pack, and polymer mortars. While a decent option for a quick fix, by their nature thin repairs generally aren’t considered a permanent or long-term repair.
Thick repairs are typically around three inches thick and at least partially encompass the existing reinforced steel. These types of repairs include replaced aggregate concrete, silica fume concrete, and replacement concrete.
Transform your concrete design project with Concreate
Durable, long-lasting concrete means making repairs the right way. Our team brings deep knowledge and a decade of experience to the residential and commercial market, working with designers and architects to repair concrete surfaces economically and with durability.
No matter the type or extent of damage, Concreate can help. From sealers and coatings to thin, thick, and crack repairs, we have the materials, experience, and knowledge to help fix your concrete problems.
Our finished concrete surfaces are stain-resistant, easy to clean, slip-resistant, and aesthetically pleasing, all due to our expertise in concrete polishing, surfacing, and repair.
Ready to bring quality restoration to your concrete flooring surface? Contact us today to learn how our concrete repair and polishing services can transform your commercial or residential project into an enduring and attractive final product.