Although the bulk of the hydration process takes place in the hours and days immediately after the pour, concrete needs 28 days to fully dry. While the slab will harden and lighten in color before 28 days, don't be fooled into thinking it's done hydrating.
Fresh concrete is always much darker than when it is fully cured and dry. Even uncolored concrete. Wait at least 7 to 10 days until the new concrete has hardened and dried. If the concrete is on a wet subgrade or there's underground water, it may stay dark for as long as it's wet.
Concrete will continue to lighten until it is fully cured. Allow the concrete to cure at least 30 days before inspecting it for color match or appearance.
Young concrete / green concrete is in the curing phase during these four weeks. Hardened concrete is called the building material after 28 days, on / with it the construction can proceed. After several months, the moisture has largely evaporated. After years the final strength is reached.
Excess Water
As the water evaporates to the surface and soaks into the cement that is an ingredient of concrete, it leaves behind darker spots where the cement contains more moisture. These will fade over time as the water eventually soaks into or evaporates out of the slab.
Bleach, Soap, and Water Mixture
Mix one cup of bleach with one cup of powdered laundry detergent, then add 15 cups of hot water. Pour your mixture over your driveway's dirty areas, such as the parts that contain oil stains. Work your mixture in using a bristle brush and scrub for approximately 20 minutes.
It can be quite frustrating when that white, chalky substance known as efflorescence or "new building bloom" shows up on your freshly poured surface. Luckily, efflorescence can be treated and removed, and prevented in the future.
Concrete that is not moist-cured at all dries too rapidly, and reaches less than half its potential design strength. It will also have a greater number of shrinkage cracks.
The dark gray discoloration is caused by varying degrees of hydration of the cement in the concrete, caused by the varying moisture contents in the localized areas of the total concrete.
Your concrete should be solid enough to walk on, without leaving footprints, after anything from 24 to 48 hours. By seven days, your concrete should be cured to at least 70 percent of its full strength.
Concrete discoloration is not a rare event
The use of too much or not enough water. The use of calcium chloride. Improper concrete laying techniques. Outside temperatures.
If the desire is to lighten the color, the best results I have seen come from pulling some of the initial stain out of the concrete. By using the carrier on which the stain is based (water, acidic water, acetone, alcohol, etc.), you can usually pull some or all of the color back out.
Water vapors that travel through the slab bring salts to the concrete surface, causing efflorescence that makes the concrete appear white. Bear in mind that vapors migrating through the slab get soluble salts, which absorb in the concrete surface.
Nope. Gets heavier. It is not “drying” it is chemically combining with water. That is why concrete cures best under water..
Stamped concrete can fade over time due to exposure to the elements and lack of proper maintenance. If an adequate exterior seal is not applied and maintained, the color of the stamped concrete can fade as a result of direct exposure to sunlight, rain, and other weather conditions.
Concrete dyes use pigments that are not UV safe and will fade when exposed to sunlight. Therefore, they are strictly used for interior projects only. Available in both water-based and solvent-based versions, they are most frequently used in the polishing process, although they can be sealed or coated like a stain.
Can I use a gray concrete and still get a white countertop? No. A true white color can only be achieved using a white cement mix. Add white concrete pigment to a gray concrete mix to create a sleek “ash” look that's popular in modern homes.
The sun will bleach and lighten the overall color of the concrete. However, local aggregate, the shape and size of the placement, and exposure to groundwater will also have an effect on the color of the concrete over time. These factors will also affect integrally colored concrete.
Read on to know more! It contains a high amount of iron oxide and manganese oxide, which end up giving the cement that classic grey colour. It contains iron and manganese, but not in oxide forms, which end up giving the cement its white colour.
Properly curing your concrete improves strength, durability, water tightness, and resistance for many years. The first 7 days after installation you should spray the slab with water 5-10 times per day, or as often as possible. Once the concrete is poured the curing process begins immediately.
Spray: To maintain the proper moisture levels, concrete should be sprayed with water frequently. This is known as moist-curing. Most specialists recommend watering the slab 5 to 10 times per day for the first seven days. Moist-cured concrete can be up to 50% stronger than dry-cured concrete.
Concrete slabs are very porous. This means standing water can easily fill in pores on the surface and eventually break down the concrete. As a result, the concrete may crack, move, or even settle.
The product's major asset, aside form its striking architectural beauty, is its ability to remain white throughout its life. White concrete, obviously, is not a surface treatment that can deteriorate with age.
The color of white cement is determined by its raw materials and the manufacturing process. Metal oxides, primarily iron and manganese, influence the whiteness and undertone of the material. After adding pigments, white cements produce clean, bright colors, especially for light pastels.
Cleansing — For mild discoloration, repeatedly flushing the hardened concrete surface with hot water, then scrubbing with a stiff brush, can reduce or remove discolored blotches. Acid treatment — If the discoloration is more severe, a mild acid solution of 1-3% muriatic acid to water can help remove the discoloration.