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Strong and durable, concrete is suited for virtually any exterior surface, while being one of the most affordable building materials. It is a mixture of Portland cement, water, and aggregates such as sand, rock, or gravel. It does have limitations, but adding calcium chloride allows the mixture to set more quickly and increases its initial strength. For concrete contractors, it improves performance and reduces costs.

Calcium chloride accelerates cement’s rate of hydration. A reduction in setting time helps protect freshly placed concrete. The effect is most noticeable in cool weather. Ready-mixed concrete sets more slowly at temperatures below 70°F, and even more so between 30°F and 50°F. This means concrete construction can continue in the fall and winter, and that contractors can still ensure quality work.

Here is a more detailed look at how calcium chloride contributes to high-quality concrete:

Effects on Chemical Properties

• Accelerated Heat of Hydration: When calcium chloride is present, the heat of hydration occurs at a faster rate, so concrete can hydrate in 10 to 12 hours.1 The total increase in hydration rate isn’t always substantial. It is more noticeable in temperatures below freezing, at which the free water content of fresh concrete is lowered faster.
• Control of Aggregate Swelling: Concrete can deteriorate due to aggregate swelling when high alkali cement is used with certain aggregates. Calcium chloride can further promote this reaction. However, if it must be used, low alkali cement or a non-reactive aggregate is recommended.
• Reduced Resistance to Sulphate Attack: Sulphates can react with calcium and aluminum ions, resulting in the formation of substances that disrupt the concrete. These include calcium sulfate and calcium sulphoaluminate hydrates. Calcium chloride can reduce resistance to this process.

Effects of Calcium Chloride on Concrete

The addition of calcium chloride to a concrete mixture in residential and commercial applications has the following effects in its physical properties:

• Setting Time: Adding calcium chloride to concrete can reduce its setting time by up to two-thirds. With a 2% admixture of chloride at a temperature of 50°F, set times attainable at 70°F without the additive can be achieved.2

Standards differ on the setting times of calcium chloride. Per the requirements of ASTM C494-1971 and CSA A266.2-1973, the initial setting time (when calcium chloride is used), should be accelerated by a minimum of 1 hour (The ASTM standard requires setting to be completed within 3½ hours, while the CSA standard requires it within 3 hours).3

• Water Cement Ratio: Calcium chloride can induce early stiffening of concrete, thereby reducing bleeding (water content rising to the top), but it does not reduce the quantity of water required to achieve a given slump or consistency. As far as the water to cement ratio, chloride does not have a significant impact on strengthening.
• Freeze/Thaw Resistance: The rapid hardening of concrete provides early resistance to freeze/thaw damage. However, calcium chloride may leave matured concrete less resistant. Nonetheless, this property is significant during the winter when freshly laid concrete may be exposed to de-icing salts.
• Air Entrainment: Less air entrainment agent is needed to produce more air content when calcium chloride is introduced. The chloride itself doesn’t cause entrainment of air.

Is Calcium Chloride Bad for Concrete in Any Way?

In addition to reduced sulfate resistance and a boost in aggregate swelling, calcium chloride can increase dry shrinkage. The contraction of hardened concrete with the loss of water can cause cracking and warping. Calcium chloride is known to increase this process. By how much depends on the type of cement, the amount of additive introduced, the curing period, and environmental conditions.

The accelerant can also trigger efflorescence. In some cases, a whitish deposit can form on cured concrete surfaces and this is not water-soluble. The deposit can be removed with diluted hydrochloric acid.

Calcium chloride can also cause corrosion of reinforcement steel. The steel is less protected when moisture penetrates the concrete, as it starts to carbonate and lose its alkalinity with exposure to air. The large surface area of the wires and greater stress differences contribute to corrosion as well.

Effects on the Mechanical Properties of Concrete

The primary mechanical impacts of calcium chloride include a gain in compression strength, especially at lower temperatures. It accelerates the hardening rate of concrete. The strength gain in the first three days may vary from 30% to 100%. However, concrete strength can decline if the amount is higher than accepted standards.

Per ASTM C-494, an increase of at least 125% at three days, over a control concrete sample, is required. This is only 90% at six months to one year after installation.4

Advantages

In summation, the advantages of adding calcium chloride to concrete on, for example, a residential concrete driveway, include:

• Accelerated rate of set
• Increased initial strength
• Prevention of freeze damage
• Reduced bleeding
• Faster workaround time
• Reduced costs
• Improved workability

When calcium chloride is added, concrete can bear loads much sooner. It is also beneficial when used with fly ash. Replacing up to half of Portland cement with fly ash can increase costs, but adding the accelerator helps. However, it is a concern when calcium chloride accelerators are prohibited under such circumstances.

How Chloride Is Added

Calcium chloride is available in many forms. It can be obtained in the form of pellets and other granules, while its flake form is also common. The flake form must consist of a minimum of 77% calcium chloride; 3¼ pounds of granulated chloride must have at least 94%.5 Solutions are recommended because all forms of calcium chloride are soluble in water.

A solution should not be in direct contact with cement, as it will set more quickly. The recommended process is to dilute the solution in water and then mix it with aggregate.

Cross Construction Services: Concrete Installation and Repair in Houston

We are experienced and trusted commercial and residential concrete contractors near you, providing patio, sidewalk, parking lot, and concrete driveway repair in Houston, TX. Concrete is a versatile material. Our over 30 years of experience, quality of work, and commitment to delivering projects on time and on budget help our clients benefit even more from our concrete service. Minimizing disruption to homes and businesses is also our priority.

Cross Construction Services is a premier concrete construction, inspection, and renewal company in your area. Call 713-254-1703 today to schedule concrete repair in Houston or obtain a free estimate.

Sources:

1. http://web.mit.edu/parmstr/Public/NRCan/CanBldgDigests/cbd165_e.html
2. http://www.tetrachemicals.com/Products/Calcium_Chloride/Applications/Ready_Mix_Concrete_Acceleration.aqf
3. http://web.mit.edu/parmstr/Public/NRCan/CanBldgDigests/cbd165_e.html
4. http://web.mit.edu/parmstr/Public/NRCan/CanBldgDigests/cbd165_e.html
5. http://web.mit.edu/parmstr/Public/NRCan/CanBldgDigests/cbd165_e.html

Concrete contractors aren’t all one and the same. There’s no one-size-fits-all approach to concrete driveway repair, and any contractor must know providing quality work requires fully understanding your project.

When searching for commercial or residential concrete contractors near you, it’s wise to ensure the company is committed to high-quality customer service. Here are some important questions to ask your concrete service contractor, so you know their experience in residential and commercial work and what to expect before, during, and after the project.

What Kind of Experience Do You Have?

Inquire about their years of experience in the field and the kinds of concrete construction projects they have completed. You can start by narrowing down your selection by reading reviews. Unless you interview a potential contractor, you won’t fully know whether they’re suited for your project. Better yet, seek contractors affiliated with reputable businesses specializing in, for example, commercial and residential concrete driveway repair near Houston, TX.

Can I See Your Portfolio of Past Projects?

Reviewing examples of the contractor’s past work helps you judge their quality and experience. If they refuse to show you a portfolio of concrete driveway resurfacing projects or evade the question, this is reason for suspicion. A reputable professional will refer you to their digital portfolio or, if you meet in person, show a series of photos on their desktop computer, laptop, or phone that exemplifies their body of work.

Do You Have References?

There may be instances when the contractor doesn’t have pictures of their previous work immediately available. Nonetheless, you can continue the conversation. Follow up with a request for references; you can also get more information by contacting previous clients. This not only allows you to get first-hand information from other customers, but it also allows the contractor to share their pride in having a list of satisfied clients.

What Is Your Current Schedule?

Knowing the contractor’s current schedule enables you to assess whether they can meet your deadline. If a quick turnaround is your priority, then you need this information. Also take into account that, if the company is reputed for quality work, they’ll understandably have a full calendar and need to schedule your project in advance.

What Is the Time Frame for My Project?

This also helps you assess a company’s experience and compare it to others. Your contact should have a good idea as to how long a project like yours will take. For example, a residential concrete driveway shouldn’t take more than two or three days, while commercial sidewalks, concrete walls, and other more extensive projects can take much longer. If one company’s estimates differ greatly from others, it’s probably a good idea to move on.

Will a Permit Be Required for My Project?

A contractor experienced in concrete construction should be familiar with the permitting process. Knowledge of the permits required for your project is necessary to produce the quality of work you’d expect. If residential concrete contractors near you can’t answer your permit-related questions, they likely lack the necessary experience.

Will the Concrete Be Reinforced with Rebar or Other Supports?

This is a good way to test the contractor’s knowledge of concrete driveway construction. The question shows your level of knowledge and lets you assess what they know. Rebar reinforcement helps support a concrete surface when the expected weight and pressure of objects is high. Plus, the more you know about the company’s process, the better informed you’ll be before signing off on the project.

What Protective Measures Do You Use?

This question provides a glimpse into their training and experience. There are many guidelines and regulations regarding work-site protection. Safe work practices can reduce the potential for delays in your project. Inquire about workman’s compensation and liability insurance, too; these can cover expenses should there be any type of job accident, which you might otherwise have to pay for.

Do You Manage the Entire Project?

Whether you’re looking for residential or commercial contractors near you, it’s important to know who is managing the project. This gives you an idea of how many concrete professionals will be on your property and who is in charge. Any experienced, organized contractor should be able to easily answer this question. If they can’t, then the contractor probably lacks the experience needed to take on your project.

Do You Provide a Written Agreement?

The written agreement should outline every detail, from deadlines to concrete driveway thickness, to prices per square foot. The contract should also indicate who is responsible for individual tasks. If you later have questions on the type or quantity of work done or the quality of service, then you’ll have a reference for what was promised to fall back on. A guarantee on the work performed can protect your investment if the work doesn’t meet predefined requirements and expectations.

Call Cross Construction Services for Concrete Repair and Installation

At Cross Construction Services, we can answer all your questions honestly and in detail. Our contractors specialize in concrete driveway repair and install concrete per the latest standards and best practices. You can trust our commercial and residential concrete driveway contractors to prepare your property, stabilize the underlying ground surface, and install quality expansion joints, not to mention fix cracks and uneven slabs and apply durable sealants. We also provide concrete leveling and install concrete for patio rooms and other outdoor living spaces.

If you’re looking for residential or commercial concrete installation or repair in Houston, TX, contact us for a free estimate and to schedule a consultation and start date.

Concrete is a highly versatile and durable solution for driveways and patios. A longer-lasting alternative to gravel driveway repair in Houston, concrete installation is beneficial in many ways. Cross Construction Services is a leader in concrete services, from construction to inspection and renovation. One of the leading concrete companies in Houston, Texas, we are committed to quality work and delivering projects on time and on budget.

When you need a concrete driveway or patio installed, you can count on us for an all-in-one solution that includes planning the project and procuring all the concrete needed. A properly designed concrete surface can improve curb appeal. To boost the value of the results, we also focus on ground stability and leveling, installing expansion joints, and fixing imperfections such as cracks and uneven slabs or drainage issues. We can reliably seal and re-surface concrete as well.

Why is concrete the best solution for patio or driveway installation? Here are five reasons why you should consider it over other materials, including asphalt.

1. Versatility

Concrete, which is used for residential applications and in business centers, shopping malls, food service establishments, warehouses, and more, is highly versatile. It is extremely resistant to variations in temperature and can withstand high heat compared to asphalt that softens and even melts. Properly sealed and maintained concrete can even hold up in extremely cold temperatures.

A strong material, concrete can withstand high traffic. That’s why it’s often used for shopping center parking lots. It can maintain integrity in heavily trafficked areas, providing safety for drivers and pedestrians. You can be rest assured our durable concrete solutions used for driveways will improve the quality of your screened-in patio or sunroom or outdoor living space.

 2. Suited for Hot Climates

Although untreated concrete can crack in extreme cold and be damaged by salt and deicers, it can tolerate temperature extremes if properly installed and sealed. Asphalt shrinks and expands with fluctuations in temperature and can easily crumble in high heat. The main difference between concrete and asphalt is how the aggregate is bound together. Asphalt is held together by a petroleum-based substance, while concrete is a mixture of crushed stone and sand bound by cement.

A hot climate does not put excessive stress on a concrete surface. If you live in an area that has long, hot summers and mild winters, concrete is the best solution. Asphalt softens up in high temperatures and can even stick to shoes and tires. Heat can degrade it along the edges, and the surface can even become indented from contact with vehicle tires.

3. Long Lifespan

Concrete can last 25 to up to 30 to 40 years.1 Most other surface materials won’t last that long, especially gravel driveways. Extremely durable, concrete can go many years without requiring a major overhaul. Substitute a plastic over a metal snow shovel, and you can avoid unnecessary damage, while acrylic sealers can offer protection against manmade damage and natural elements.

However, sealing is not required. It all depends on where you live and how your property is used. If you don’t need a sealant, some costs can be saved, but it can extend the life of your concrete. Although concrete must be at least four inches thick, adding one inch of thickness increases the load-carrying capacity by about 50%.2 When the material is at the end of its usable life, it can be recycled and installed all over again.

4. Ease of Maintenance

If you’re looking for minimal maintenance, concrete can meet your expectations. As stated earlier, it does not require resealing, but a reseal job every five years can extend its life (by contrast, asphalt must be resealed six months after the initial installation, and then every three to five years).

Driveway sealing is a good way to prevent stains and make a concrete surface resistant to salt and deicing chemicals. The only required practice is regular pressure washing. It can improve the appearance of the surface by removing fluids that have leaked from vehicles, discoloration due to mold and mildew, and leaves that pile up in the fall.

5. Can Be Resurfaced

Over time, cracks, gaps, and uneven segments can degrade a concrete driveway in Houston. Crumbling edges and poor drainage can take a toll as well. Small cracks and holes can be patched up, but it is often hard to hide areas that have been treated. A complete resurfacing can be costly, but, with the entire top layer removed and replaced, any crack or break can be hidden.

At Cross Construction Services, our experienced technicians can restore your concrete driveway or a parking lot by addressing minor issues early. Our team performs a complete assessment before doing any repair work. The latest processes and materials are used, while we can address defects in expansion joints, drainage, plumbing, and retaining walls or hand railings.

Hire Cross Construction Services

We are experts at installing home concrete driveways and patios to optimize your living space for enjoyment during long, hot Texas summers. The durability of concrete cannot be beat. When cracks develop, we can repair your patio or driveway to ensure it is safe for you and your family.

Whether you require patching, resurfacing, or replacement, our specialized team can do the work and leave behind exceptional results. If you’re looking to benefit from the durability, versatility, and longevity of concrete for your home or business, contact Cross Construction Services today at 713-254-1703 or contact us online for a free estimate.

Sources:

1. https://www.homeadvisor.com/r/asphalt-vs-concrete-driveway/
2. https://www.homeadvisor.com/r/asphalt-vs-concrete-driveway/