During concrete hollow blocks producing, many people usually think about how to cure concrete hollow blocks after producing by hollow block machine, here are some tips：
1.Basic requirements for maintenance:
After the concrete is poured, the sunshade cloth or watering must be wrapped in the steel mold to cool down, and the concrete surface should be covered immediately for heat preservation and moisturizing. When the temperature is high (above 10 °C), the early maintenance of the concrete structure adopts hydration and health preservation. During the curing period, the water storage material should be regularly filled with water to ensure continuous moisturization, the health time should not be less than 14 days, and the health should be extended as much as possible. Time to ensure the early hydration quality of concrete; when the temperature is low (below 5 °C), in order to ensure the quality of concrete structure maintenance under low temperature conditions, a closed curing process is adopted, and the curing time is not less than 28 days; the concrete is strictly controlled. The curing temperature is not lower than the minimum applicable temperature specified by the concrete admixture. When the ambient temperature is lower than - 5 °C, insulation measures (such as covering with dry cotton) should be taken until the strength of the concrete reaches the critical frost resistance, and Concrete sprinkler. After the pouring is completed, it should be cured within 12 hours; before the strength of the concrete reaches 40% of the design strength, it is strictly forbidden for anyone to walk on it and install the template bracket, and it is not allowed to be impact or any beating operation.
After concrete is poured, the reason why it can gradually set and harden is mainly because of the result of cement hydration, while hydration requires proper temperature and humidity conditions, so the strength of the concrete is increased to ensure proper hardening conditions. Concrete must be cured. The purpose of the maintenance of concrete is to create various conditions to fully hydrate the cement and accelerate the hardening of the concrete: the second is to prevent the abnormal shrinkage, cracks and other damages caused by exposure, wind blowing, cold and other conditions after the molding.
After demoulding and curing, after the concrete structure is demolished, the exposed concrete surface should be quickly covered with plastic cloth and other materials for maintenance. When covered with plastic cloth, the curing should be no less than 14 days. In the cold season and hot season, appropriate thermal insulation measures are taken to ensure that the temperature difference between the core and the surface layer, the surface layer and the environment during the curing period does not exceed 20 °C.
2.Maintenance process
Coverage curing is the most commonly used method of moisturizing and moisturizing. The main measures are:
Covering the curing after initial setting, starting to water after the final setting (about 12 hours later), the surface of the poured concrete (including the structure without demoulding) is covered with a layer of water storage material (such as sacks, quilts, etc.) ), covered with plastic film, covered with straw bags, straw curtains, black cotton, rotten mats, sacks, fabrics, color strips, etc.
Watering tools can use tools such as water pipes, buckets, and small pumps to ensure the wetness of the concrete.
3.Maintenance time
The curing time is related to the concrete part, the cement type and the presence or absence of admixture. The commonly used cement is not less than 7 days under normal temperature conditions; the project with admixture or anti-seepage and anti-freezing requirements is not less than 14 days.
4.Maintenance method
Under normal temperature conditions in summer, the concrete of the pier is covered with water, and the film is wound from top to bottom. Each circle overlaps and is tightly wrapped. The top of the pier is sprinkled to ensure the concrete is wet. When the temperature is low, take cover warming measures (wrapped with black cotton and colored strips). In the early maintenance of concrete, it is necessary to prevent contaminated concrete such as black cotton. The curing time depends on the growth of the concrete strength. When the curing period is full, the covering can be removed and the concrete surface should not be left with traces. Winter construction measures are taken in winter, see winter construction measures.
