Wet the concrete, then place the plastic sheeting over it. Use bricks, boulders, or stakes to hold the plastic in place and keep small animals out. Once a day, remove the plastic sheet and wet the concrete, then replace the cover. Do this for a week for the best results.
The most efficient way to cure concrete is to use a plastic cover. The covers are placed on freshly poured concrete until the concrete has a chance to dry. Plastic concrete curing covers seal off concrete and prevents water from evaporating.
When the temperatures drop, new concrete should be covered with concrete insulating blankets (or, in a pinch, old household blankets!). Protect new concrete from the cold for the first two to three days—up to a week, if it's very cold—after which it should be strong enough to handle it without risk of damage.
Curing time of concrete is typically 24-48 hours, at which point it's safe for normal foot traffic. After one week, concrete is typically cured enough to handle continued construction including heavy machinery. Concrete is recognized to have reached full strength 28 days after placement.
Protect Concrete from Rain
If too much rainwater falls over recently placed concrete before it is set, it can weaken the concrete strength. Therefore, it is necessary to cover and protect freshly placed concrete during rains.
To put it simply, the goal is to keep the concrete saturated during the first 28 days. 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.
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.
Concrete typically takes 24 to 48 hours to dry enough for you to walk or drive on it. However, concrete drying is a continuous and fluid event, and usually reaches its full effective strength after about 28 days.
Moist curing is a common method of concrete curing. It involves wetting the concrete slab often with water (5-7 times per day) for the first 7 days. This method ensures your concrete slab will be extremely strong and durable, because it allows the moisture to evaporate slowly, preventing cracks and shrinks.
Keeping concrete moist is essential to the concrete curing process, but too much water and the concrete may not form in the way it needs to.
If your concrete mix is too wet it will also be more porous once cured, making it difficult to achieve the desired finish and potentially making it not fit for purpose. In short, a concrete mix that is too wet could seriously impact the durability, longevity and strength of your project.
“Without a vapor barrier, concrete will deteriorate much faster through water vapor intrusion which degrades the quality of the concrete over time and can lead to foundation and building failures, like Surfside Condominium Collapse in Miami, Florida,” says vapor barrier plastic sheeting expert and Americover account ...
Using synthetics like plastic in concrete generally weakens the material because they do not bond to the cement mix as well as sand.
They discovered that replacing sand with plastic bottles ground up into similarly sized and shaped particles resulted in concrete that was almost as strong as conventional concrete mixtures, and it could save 820 million tons of sand per year and reduce plastic waste levels.
For concrete to dry and reach its full strength, it typically takes about 28 days per inch of slab thickness. Once conditions are conducive for the concrete to cure at 85-90% relative humidity.
If concrete forms are removed too early, the concrete may not gain enough strength sufficient for handling the required loads. However, you can't leave concrete forms on too long in a way that would compromise the integrity of the structure and load-bearing process.
HOW DOES RAIN AFFECT CONCRETE? Rain falling on top of freshly laid concrete can damage the surface and compromise a level and floated finish.
You should wait at least 24 hours before walking on your freshly poured concrete. However, make sure not to drag your feet, twist around on it, or let your pets with claws walk on it until later. Bikes, toys, and skateboards should also be kept away from the driveway.
It is not what concrete does if it is left to do whatever it will on its own. Curing is a thing that you do to concrete. Concrete needs moisture to hydrate the cement. Without that moisture, the strength will be less than it should be.
When too little water is used or if water evaporates out too quickly, the cement never reaches a full chemical cure, causing a weakened product.
In residential concrete, 4 inches is the minimum thickness for walkways and patios. Garage slabs and driveways should be 5 to 6 inches thick if any heavy truck traffic is anticipated, otherwise 4 inches is adequate.