ELAZIG GUNISIGI NEWSPAPER –July 2012
THIRST
We are experiencing the hottest days of the summer season. The most essential food items we need during this time are beverages, especially water. Due to Ramadan, I believe we've all come to appreciate the value of water even more. Water is not only crucial for living beings but also for certain inanimate substances. For example, the materials we use to build our homes, the places where we spend our lives, like concrete, rely on water.
One of the biggest challenges faced by the Turkish Republic since its establishment has been urbanization and settlement. Financial and technical limitations have been some of the biggest barriers to urban development. Once these barriers were overcome and urbanization began, many serious deficiencies grew, either due to oversight or neglect. We, as a nation, have paid the price for these shortcomings in many earthquakes. Together, we’ve borne the cost. As much as we can, we are trying to highlight the deficiencies and solutions regarding both the existing building stock and newly constructed buildings.
We are in the summer season, and especially during the daytime in our city, there are extreme weather conditions that affect concrete pouring and curing. Concrete is the most affected material by these conditions. Even if concrete is produced well, if the curing conditions are not suitable, the actual strength will never match the expected strength! Just as a person needs more water in hot weather, concrete also needs more water to reach the desired strength.
It’s time again (though I realize it probably won’t be the last!) to reiterate the necessary information in clear terms so that we can address the significant deficiencies we are facing in this area.
Does concrete need to be watered (cured)?
Concrete is made of water, cement, sand, and gravel. Water and cement react with each other, and this reaction produces heat. If the heat inside the concrete is not reduced, the water inside will evaporate, leading to lower concrete strength. To allow concrete to cool and reach the desired strength, it must be watered after setting.
Does concrete need to be watered in every season?
After concrete has been poured under suitable conditions, it must always be cured. In hot weather, the curing process should be extended for a longer period.
When during the day should concrete be watered?
Concrete samples are kept in curing pools for 24 hours and up to 28 days, so there is no specific time limit for watering concrete. However, watering at midday will cause a significant portion of the water to evaporate. Additionally, working with formwork in a wet environment becomes difficult, so it is recommended to water concrete during the morning and evening. This does not mean that watering at noon is prohibited, but it should be avoided when possible.
How much water should be used for curing in construction?
Concrete should not be watered excessively like a lawn. The amount of water must be sufficient to reduce the heat of the concrete without allowing it to evaporate from the surface. Curing should be done by qualified personnel, or the workers performing the task should be informed and trained on the subject.
Is watering only the floor enough?
One of the most common mistakes is only watering the floor. Just like floors, columns, walls, and beams are also made of concrete, and these elements have the same properties as the floor. Therefore, both the top and bottom of the newly poured floor should be watered until the concrete’s temperature drops. (Sadly, in Elazığ, you can be sure that this practice is rarely done. No curing process is done on the underside of the floor in intermediate floors.)
How long should the curing process last?
Standard minimum curing times have been established. However, factors like ambient temperature, cement dosage, type of structure, type of cement, wind, and humidity can affect these times. Therefore, the curing process should be done in a way that minimizes the difference between the real structure and the samples. For residential buildings, it is recommended that the curing period for each floor last no less than 21 days.
What happens if curing is not done in construction?
The concrete's strength will decrease by at least 40%. This represents both material and moral loss, as well as a loss in national wealth.
Which elements in the rough construction should undergo curing?
Curing starts with the concrete under the foundation's reinforcement layer. All concrete elements on each floor must undergo the curing process. Additionally, all mortar used in walls, both for plaster and finishes, should be cured. This means that curing should continue until the rough construction is complete. Any material containing cement must be watered.
Construction inspection firms have a huge responsibility in this matter. Please, let’s all take responsibility when it comes to concrete curing…
What may seem like an insignificant detail, or something trivial, can be the beginning of the end. Let’s cure ourselves of the illness of neglect. Let’s take things seriously…