In the future, concrete pouring on rainy days will be generally prohibited to enhance the safety of construction structures. If the average daily temperature is below 4℃, measures to ensure additional strength must be carried out when pouring concrete.
The Ministry of Land, Infrastructure and Transport announced on the 17th that it will revise the concrete construction standards, including the standard specifications and design criteria applicable to apartments and buildings. The revised standards are expected to be announced within the year after collecting opinions by the 26th.
The core of this revision is to establish work standards that must be adhered to on-site to ensure quality when performing concrete construction in rainy weather and in cold environments with an average daily temperature below 4℃.
Accordingly, if there is a concern about quality deterioration due to rain, concrete pouring will be prohibited. However, if pouring is unavoidable, measures to prevent quality deterioration from water ingress must be taken in accordance with the newly established "guidelines for concrete pouring in rainy weather," and approval from the responsible technician is required. The Ministry of Land has set a specific rainfall standard of 3mm per hour to determine whether or not concrete pouring can take place on-site to prevent confusion at construction sites.
Taking into account the characteristics of materials that do not exhibit sufficient strength in cold environments with an average daily temperature below 4℃, the Ministry of Land established new standards based on real-world verification research results to ensure adequate strength. When pouring concrete in cold environments, an additional strength of 6 megapascals (MPa) must be secured. Megapascal (MPa) is a unit that indicates concrete strength, with 1 MPa representing a pressure of 100,000 newtons (N) per square meter. In cold environments, the maximum usage ratio of mineral admixtures that inhibit the development of concrete strength is also reduced.
However, in cases where it is proven that the target strength can be achieved by using new materials or technologies, the temperature-adjusted strength or the usage ratio of admixtures may be exceptionably adjusted with the approval of the responsible technician.
The Ministry of Land will mandate the production and testing of field curing specimens when pouring concrete at construction sites. Previously, field curing specimens were produced only when required by the responsible technician. Field curing specimens refer to samples made under the same conditions as the construction site to verify the appropriateness of concrete pouring and curing. Additionally, the evaluation standards that were uniformly applied have been reasonably improved, and design standards for the introduction of new technologies in response to climate change have also been established.
The Ministry of Land will actively inform local governments, project owners, and construction-related associations about the revised concrete standards, and plans to collaborate with organizations such as the Korea Concrete Institute and the Construction Engineering Association to provide training on concrete standards for on-site technical personnel.
Kim Tae-byeong, director of technical and safety policy at the Ministry of Land, noted, "Quality management of concrete is crucial for ensuring the safety of construction structures such as dwellings, bridges, and tunnels. We have gathered opinions through various channels multiple times to enhance on-site acceptance of the revised standards. We request that construction projects adhere to the newly introduced standard revisions to ensure safer execution of construction work."