Doosan Engineering & Construction Co. said on the 5th that it has obtained a patent (registration No. 10-2931349) for a jointly developed "concrete composition for placement in rain including an admixture that maintains strength during rainfall and reduces drying shrinkage" with Aju Industrial. This technology is the first among construction companies to obtain a patent for securing concrete quality in rainy conditions.
In general, the strength and durability of concrete are determined by the water-to-cement ratio. If external moisture enters during placement, the designed mix ratio changes, the cement concentration becomes relatively lower, and segregation and strength loss can occur. This can lead to potential problems such as surface quality deterioration, increased cracking, and reduced long-term durability.
Considering these quality risks, the "guidelines for concrete placement during rainfall" published by the Ministry of Land, Infrastructure and Transport allow concrete work during rainfall of 3 mm per hour or less after taking appropriate measures to prevent moisture ingress, and stipulate that if it exceeds 3 mm per hour, placement must be stopped and appropriate protective measures taken.
Doosan Engineering & Construction Co. developed a technology that suppresses external moisture ingress even during rainfall to minimize changes in the water-to-cement ratio and reduce segregation and strength loss. Through this, the company made it possible to secure quality stability even under rainfall conditions that exceed government guideline standards.
Doosan Engineering & Construction Co. confirmed through certified testing agency performance tests and full-scale building slab member tests that it secured stable compressive strength meeting design criteria even under rainfall conditions of up to 6 mm per hour, which exceeds the government guideline standard of 3 mm per hour. The patented technology is expected to serve as an alternative to ensure a certain level of construction continuity and quality stability even amid recent changes in weather conditions, helping to mitigate potential schedule delays due to rain and enhance confidence in on-site quality control.
Doosan Engineering & Construction Co. said, "Quality technology competitiveness to respond to recent changes in weather conditions is becoming increasingly important," adding, "With this patent, we have secured reliable construction quality even in rainy environments, and we will continue to strengthen technology development to respond to changing weather conditions."