Three days of pond curing does the work of seven days of moist curing, and without daily attention—just be sure the water level remains above the concrete slab. Large-scale builders may use this method to speed up the construction process when pouring foundation slabs, for example, in order to get on to framing the structure. Available from DIY stores and ready-mix concrete companies, these contain soluble emulsions that form a protective film when sprayed directly onto the surface of newly poured concrete slabs or walls.
Ultimately, the film provides a barrier or film to prevent water from evaporating, allowing it to cure at a consistent rate. Some curing compounds are designed to disintegrate completely after a couple of weeks, while others should be removed by scrubbing after the curing process is complete. The goal of all concrete installation is to produce a high-quality product that resists cracking. While curing concrete will go a long way toward strengthening the finished project, many concrete slabs will crack anyway—despite all precautions—due to concrete shrinkage as water is used up in the hydration process as well as temperature fluctuations.
To preserve the beauty of the slab in the face of these challenges, do-it-yourselfers can place control joints at predetermined locations to guide the inevitable cracks.
These joints should be cut in a quarter of the depth of the concrete slab during the very beginning of the curing process, within 24 hours of the initial pour. Using a metal jointing tool, the control joints can be easily and smoothly cut into the concrete surface as the appropriate distances in the slab.
Determine the maximum spacing between joints in feet by multiplying the planned concrete thickness in inches by 2. Feel free to place them closer together for added crack protection. Then, if your slab patio, driveway, or sidewalk cracks, it will most likely do so along a precut joint and can, therefore, go virtually unnoticed. The best time to pour concrete is when temperatures are expected to remain above 50 degrees for five to seven days, but plans can go awry with the arrival of an unexpected cold front.
However, for practical purposes and a timeframe shorter than infinity, here are some general rules of thumb where curing is concerned. Typical industrial concrete will recognise its full workable strength at the 28 day mark.
For those who are laying concrete in a domestic area, like the garden, concrete is reasonably set within hours. Leave that until after the 28 day period. There are many things you should guard against while laying concrete and allowing it to cure.
For the best results, it is always ideal to employ a professional for the job. If you are looking for professional results, employ a professional in construction or a concrete specialist. There are many ingenious ways to ensure concrete is cured correctly, including: ponding, sprinkling, wet coverings, sheet curing, membrane curing and air drying.
It will depend what your concrete is being used for as to what method is used. So, if you are unsure about your concreting skills, make sure to consult the experts for results that are guaranteed to satisfy. I watched Brish builders pouring concrete into house foundation trench that was so wet it looked like dirty water! British climate is generally wet so how coudl such a mix have much strength? What about fence post brackets set into concrete? How long should one wait before fixing the wooden posts onto the brackets?
Would 7 days be long enough to wait? How long should we wait before applying stain on top? Concrete Blankets, Interesting! I am going to take a look more deeply into that.
That might be something we could use for some jobs we do. Just for the record! I have poured Cement under water successfully. I was asked to lay a Pylon for a small jetty many years ago and was unsure how to begin the job. I then braced the pipe and back filled it with a Strong cement dry cement mixture roughly allowing for some of the Cement Powder to wash away is the process. Having finished the pour I then back filled the gap about the pipe base and left the whole thing for a week to set.
Keep in mind that in hot weather keeping cement moist allows for a slower drying time to gain a strong job and once the the mix had been laid there was no way for water to get in or out of the pipe once the mix began to go OFF.
Trust too Providence you got it right. Through Floods and drought that pier is still standing 20 years later. Did I get it right?? Only time will tell.
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