02 Dec Is Quick Set Concrete Strong?
Quick Set Concrete is known for curing considerably faster than normal ones. However, a common concern among builders is whether this speed sacrifices strength. This guide explains the phenomenon in detail, clarifies where and how to use Quick Set Concrete, and tips for maximizing its strength.
Yes, Quick Set Concrete is strong. If used correctly, it may become even stronger and more durable than a traditional one.
Keep reading to learn how strong Quick Set Concrete really is, the factors that influence its strength, and the best time to use it.
How Strong Is Quick Set Concrete?
The strength of Quick Set Concrete can be divided into two phases:
Initial Strength:
Quick Set Concrete normally achieves 4000 psi within 24 hours. It is more than sufficient strength to perform quick repairs.
Full Strength:
It typically reaches its full strength within 7 to 28 days, depending on several factors. A high-quality Quick Set Concrete exceeds 7000 psi in 72 hours and continues to get stronger, even after 28 days.
Factors That Impact Quick Set Concrete’s Strength
These factors influence how strong Quick Set Concrete will be after it’s fully set:
Mix Ratio:
Quick Set Concrete requires the exact water-to-mix ratio as instructed by the manufacturer. For example, QUIKRETE recommends using approximately 2.8 liters of water per 36.3 kg of dry mix. An extra liter of water can reduce the concrete’s strength by 40%. Such guidelines may vary with brands.
Curing Conditions:
Certain conditions must be met to cure Quick Set Concrete properly. Make sure there’s moderate temperature, sufficient moisture, and minimal wind before curing.
Temperature:
A temperature between 10 and 21 degrees Celsius is considered moderate by the American Concrete Institute (ACI). Too much heat causes cracks and near-freezing temperatures slow down the hydration reaction.
Product Quality:
The quality of Quick Set Concrete varies with every manufacturer. It’s not certain that all mixes will have the same formulation. Understanding product specifications clarifies whether the product you choose has balanced ingredients.
Applications That Prove Quick Set Concrete’s Strength
Quick Set Concrete is not only suitable but essential for specific applications that require strength and speed.
Emergency Repairs:
Quick Set Concrete is widely used to repair public service infrastructure like roads and bridges, where downtime isn’t an option.
Setting Posts:
It helps set up fences, lamp posts, traffic lights, sign poles, and football or basketball posts immediately. You can be confident that these structures will work as expected. Only a force majeure will be able to harm them.
Patching Cracks and Holes:
Quick Set Concrete provides a faster way to fix damaged infrastructure. It can quickly patch floors, pathways, and stairsteps while ensuring they don’t get damaged easily in the future.
Underwater Repairs:
The formulation of Quick Set Concrete also makes it waterproof. This makes it ideal for repairing submerged structures where normal concrete can’t help. These include foundations, drains, offshore rigs, and piers. Every structure can withstand heavy underwater pressure when applied with this concrete.
Is Quick Set Concrete as Strong as Traditional Concrete?
Quick Set Concrete may harden faster than traditional concrete, but its long-term strength is often similar. This is why Quick Set Concrete is best for small to medium scale projects.
For Structural Applications:
Even if Quick Set Concrete surpasses traditional ones in strength, it is not recommended for structural use. Conventional concrete is still preferred for large-scale projects. It is due to its stronger bond with reinforcement bars (rebars). This bond is vital for making structures like foundations and skyscrapers durable.
Quick Set Concrete contains accelerators like calcium chloride to speed up the curing process. Such mixtures can corrode the rebars required to provide tensile strength to the concrete building.
Over time, this corrosion leads to cracks, breaks, and eventual collapse. Even the American Concrete Institute (ACI) recommends using regular concrete for reinforced applications.
For Repairs and Small Projects:
Quick Set Concrete excels in repairs and small projects where reinforcement is not required. In such applications, timing and fast results matter more. Quick Set Concrete is engineered to do exactly that.
It saves considerable time as it comes ready-mixed in a bag. You just have to add the mentioned amount of water and get to work. The faster curing time of Quick Set Concrete also saves labor costs and allows businesses to complete more projects in less time.
Tips to Maximize Strength of Quick Set Concrete
Here’s how you can maximize the strength of Quick Set Concrete:
- Use Quality Products:
Make sure you select a reputable manufacturer of Quick Set Concrete. Trusted sellers use high-quality materials to create their mix. Ingredients normally include quick-setting cement, PVA fibers, superplasticizers, and shrinkage-reducing agents (SRAs).
If Quick Set Concrete is of low quality, it will have a flawed composition. It may include the wrong water-to-cement ratio, weak aggregates, and conflicting additives. Poor formulations result in unpredictable setting time and insufficient compressive strength.
- Follow Mix Instructions:
Use the exact water-to-mix ratio recommended by the manufacturer. This instruction is present on the product’s label. Avoid the common mistake of pouring the same amount of water as in the regular concrete.
- Cure Properly:
You need to take special care during the curing process. Do not proceed if the temperature is below 4 degrees Celsius. It slows down hydration and doesn’t develop the full strength of Quick Set Concrete.
Moreover, make sure to apply curing spray within the first 15 minutes of mixing. It saves the concrete from drying too soon. Furthermore, use insulated blankets in cold weather to prevent moisture from evaporating.
- Avoid Overworking:
Avoid overworking Quick Set Concrete after mixing it with water. Spreading the material too much on the surface leads to weaker adhesion. This is the reason why cracks are formed on the structure.
Conclusion
To conclude, Quick Set Concrete is a strong material. But, only for repairs and small-scale projects. It cannot bond with steel to support the tensile load like normal concrete does. Thus, conventional concrete remains the default building material for structural use.