What is cement and concrete?

What does it mean to "cure" concrete?

Why does concrete crack?

What are the joints in a concrete driveway?

Can it be too hot or too cold to place new concrete?

Should concrete driveways be cured?

Is it harmful to use salt to remove ice from a concrete driveway?

When can I use my new driveway?

How long should my concrete last?

How do you remove stains from concrete?

What are the decorative finishes that can be applied to concrete surfaces?

 


What is cement and concrete?

Cement and concrete often are used interchangeably however cement is actually an ingredient of concrete. Concrete is basically a mixture of sand and gravel or crushed stone and a paste of water and portland cement. Cement comprises from 10 to 15 percent of the concrete mix, by volume. Through a process called hydration, the cement and water harden and binds it all into a rocklike mass. This hardening process continues for years meaning that concrete gets stronger as it gets older.
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What does it mean to "cure" concrete?

Curing is one of the most important steps in concrete construction, because proper curing greatly increases concrete strength and durability. Concrete hardens as a result of hydration: the chemical reaction between cement and water. However, hydration occurs only if water is available and if the concrete's temperature stays within a suitable range. During the curing period-from five to seven days after placement for conventional concrete-the concrete surface needs to be kept moist to permit the hydration process. New concrete can be wet with soaking hoses, sprinklers or covered with wet burlap, or can be coated with commercially available curing compounds, which seal in moisture.
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Why does concrete crack?

Concrete will slightly shrink in volume when it dries out. In typical concrete this amounts to about 1/16 of an inch in 10 feet. This shrinkage produces a tension force within the slab and the concrete can and will tear itself apart just as you can tear a piece of paper. Using joints in the concrete helps to minimize this.
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What are the joints in a concrete driveway?

These are known as control joints and give your concrete a place of least resistance to cracking. Should cracking occur, it should crack along the joint first and hopefully not in random places. They are placed every 10 feet and are either ridged or cut into your cement.
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Can it be too hot or too cold to place new concrete?

Absolutely! Temperature extremes make it difficult to properly cure concrete. On hot days, too much water is lost by evaporation from newly placed concrete. If the temperature drops too close to freezing, hydration slows to nearly a standstill. Under these conditions, concrete ceases to gain strength and other desirable properties. In general, the temperature of new concrete should not be allowed to fall below 50 Fahrenheit (10 Celsius) during the curing period.
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How long does it take to install a driveway?

Most average sized concrete driveways are removed and replaced in the same day. Removing the forms and backfilling happen on the 2nd day. Paver driveways will also take about 2-3 days. Stamped concrete driveways usually take 4-5 days. Weather can also be a factor.
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Should concrete driveways be cured?

Curing of concrete is the final step of the construction process, and one of the most important. Curing or keeping the surface moist to assure greatest hydration of cement and highest potential strength is easily done through spray membranes or other readily available products and procedures. Curing compounds should be applied after the final finishing operation to increase the concrete's resistance to the effects of weather, and to decrease the occurrence of surface defects.
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Is it harmful to use salt to remove ice from a concrete driveway?

If possible, avoid the use of salt on your driveway, especially during the first winter. This is very important if your driveway was built in the fall of the year. Do not use products containing ammonium nitrates to de-ice your driveway. Snow blowers and shovels work the best on your new driveway.
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When can I use my new driveway?

Depending on the temperature you can use your new concrete driveway 7 to 10 days after the concrete has been poured. 7 days during the hotter months of the summer and 10 days during the milder temperatures of the spring and fall.
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How long should my concrete last?

Properly maintained and cared for concrete should last 20 plus years.
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How do you remove stains from concrete?


Common dry methods include sandblasting, flame cleaning and shotblasting, grinding, scabbing, planing and scouring. Steel-wire brushes should be used with care because they can leave metal particles on the surface that later may rust and stain the concrete. Wet methods involve the application of water or specific chemicals according to the nature of the stain. The chemical treatment either dissolves the staining substance so it can be blotted up from the surface of the concrete or bleaches the staining substance so it will not show.
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What are the decorative finishes that can be applied to concrete surfaces?

Color may be added to concrete by adding pigments-before or after concrete is place-and using white cement rather than conventional gray cement, by using chemical stains, or by exposing colorful aggregates at the surface. Textured finishes can vary from a smooth polish to the roughness of gravel. Geometric patterns can be scored, stamped, rolled, or inlaid into the concrete to resemble stone, brick or tile paving. Other interesting patterns are obtained by using divider strips (commonly redwood) to form panels of various sizes and shapes. Special techniques are available to make concrete slip-resistant and sparkling.
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