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Starting today (the 20th), we are going to take a look at the various problems at the construction site that were revealed in the wake of the collapse. First of all, the concrete pouring work in winter was pointed out as the cause of this accident.
Reporter Sohn Hyung-an covered how work was done at the construction site on a cold day, its problems and alternatives.
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A construction site in the metropolitan area where an apartment complex will be built.
The period of concrete pouring and curing, which used to be piled up one layer a week, was increased to two weeks immediately after the Gwangju collapse accident.
[Field worker: Losing a cow and fixing a barn, or even before that, I wonder if the cycle would have been a week because of the air, even though it needed a curing period of two weeks.]
Unlike general concrete in winter, the speed of hardening by mixing admixtures is lowered at construction sites .
Quickly use Korean-Chinese concrete.
However, the curing method must be followed, such as keeping the surrounding area at least 5 degrees when pouring.
Otherwise, the concrete will not harden properly and the building will become weak due to microscopic freezing inside.
However, field workers say that this principle is not well followed.
[Field worker: Sometimes there is thin ice in the sub-zero range. During the pouring time, the concrete continues to be exposed to sub-zero temperatures and pouring proceeds. I also thought that there might be a problem with the product (concrete).]
In Korea, the construction period of high-rise apartment complexes usually does not exceed three years.
Since expensive winter concrete is used to continue construction even in winter, the construction progresses at a faster pace in order to reduce the worker's daily wage.
[Field worker: From the perspective of the construction company, that is the (air) promise.
It's a promise to the tenants, and if you don't keep the promise, you'll be charged a deductible, and there are things like that.]
Experts say that the winter frame construction poses a fundamental risk of poor construction.
[Lee Jun-sang/Chairman of Gwangju Jeonnam Headquarters, Construction Union of the Federation of Trade Unions
] There are also opinions that the construction should be stopped depending on the weather and the weather.
[Hancheon-gu / Chair Professor, Department of Architectural Engineering, Cheongju University: Rain, snow, and wind.
If there is no choice but to do it, there are various regulations that come with it, and we should proceed with the construction while complying with the regulations.]
Experts emphasize that it is time to establish a new principle for construction sites with safety as the top priority.
(Video coverage: Kim Heung-sik, Video editing: Park Ki-duk, VJ: Kim Jong-gap)
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