Within 20 seconds of the collapse of the sky and the earth, nearly 1,500 people were crushed under 42,000 tons of rubble.
This is the collapse disaster of Sanfeng Department Store that occurred in 1995, and it is also the biggest casualties in peacetime in South Korea.
This collapse caused a total of 3502 deaths and 937 injuries, and economic losses of 66.7 billion won .
Angry people took to the streets to protest, dozens of government officials were charged with corruption.
Today, the name of Sanfeng Department Store is still a scar that many Koreans do not want to uncover.
How did this shocking disaster happen?
That was 1995, and the South Korean economy was in the period of rapid development of .
Due to the combined effect of factors such as surge in exports and continued active domestic consumption, South Korea's GDP growth rate reached 9%.
In recent years, various commercial buildings have emerged like mushrooms after a rain.
Sanfeng Department Store , built by South Korea's Sanfeng Group, is one of the best.
It is located in a prime location in Seoul, with more than 1,000 employees, and the main consumer group is office workers in the capital.
This luxury department store has five floors above ground and four floors underground, with an average daily customer service of 40,000, and a weekly turnover of million .
Disaster happens when the department store opens for 5 years.
June 29, 1995 at 8 am, the department store’s facility manager Li Yongzhou came to the office as usual.
He noticed a note left by the night guard on the table, which mentioned the strange noise from the rooftop last night.
Li Yongzhou knows that it was a crack left by when he moved the air conditioner on the roof two years ago.
But Sanfeng Department Store has just passed regular safety inspections, so he didn't take it seriously.
Two hours later, Chunyuan Restaurant located on the fifth floor of the mall contacted Li Yongzhou .
They found that there were huge cracks around a pillar in the restaurant, and the width could actually be stuffed into a fist .
Li Yongzhou decided to temporarily close the restaurant and instructed employees to remain silent to avoid panic among everyone.
The day before the collapse, the sloping restaurant floor
customers who consumed in department stores also felt an unusual vibration.
After receiving feedback from customers, Li Yongzhou believes that this may be caused by the air conditioner.
So at 12:30 noon, he closed the air conditioning in the building.
At the same time, Sanfeng Department Store broadcasted the news of air conditioner failure to customers and employees.
0 0 pm, Sanfeng Group Chairman Li Li convened all supervisors to discuss measures for cracks and vibrations in the building.
They invited the structural engineer in charge of building the building Li Hezhu to check the cracks.
Li Hezhu found that the crack had expanded to the roof of the entire building, and some areas also experienced small collapses.
After carefully assessing the risks, Li Hezhu believes that the building should be closed immediately and urgently repaired.
But his proposal was quickly rejected because management was reluctant to lose a substantial turnover of the day.
What they don't know is that this decision will trigger even more terrible consequences of .
It was evening, and people from get off work rushed into Sanfeng Department Store. This was the peak business in the day.
Busy customers filled the counters of the department store.
5:40, a rumbling sound came from the roof of the building.
More than 1,500 people in Sanfeng Department Store have not realized that the building is on the verge of collapse .
7 minutes later, a bigger burst sound came from the roof of .
is located on the fifth floor of Chunyuan Restaurant , and the floor slab is penetrated by columns and is no longer able to bear more weight. The load that is extra out of
is shared by other columns, but it obviously cannot last long.
5:52, the alarm in the building was made, and Sanfeng Department Store finally collapsed.
People panic in the alarm and roar toward the exit, but everything happened too quickly .
In less than 20 seconds, each floor collapsed continuously and hit the ground heavily, bringing a lot of smoke and dust.
Once a symbol of Seoul's prosperity, it has now turned into twisted steel bars and rubble.
shocked passers-by rushed up the rubble to rescue the mildly injured survivors.
A few minutes later, police cars and ambulances also flocked to the scene of , and the scene of was in chaos.
A total of five floors of wreckage were pressed above the four underground floors, and the number of people buried was immeasurable.
Because of concern that heavy bulldozing will hurt the buried person, the rescuers could only move the gravel with bare hands.
Some large cranes also arrived at the site and began to carefully lift the building wreckage.
By the early morning of the next day, more than 200 survivors were rescued, but the death toll was also rising.
In addition to rescue workers, there are also investigators of the accident who are busy at the disaster site.
They were eager to know what caused such a serious collapse of Sanfeng Department Store, which had been built for only 6 years.
This may be related to the safety of high-rise buildings in Seoul and even across the country.
After excluding the possibility of earthquakes and terrorist attacks, investigators suspected that there was a problem with the foundation strength of the building.
The original site of Sanfeng Department Store was an landfill , and its weak soil layer was likely to cause collapse.
But the survey shows that the foundation location of the building is very accurate and the strength is not a problem.
Investigators began to turn their focus to the building itself.
They collected about 150 sets of concrete samples in rubble piles and tested their strength in the laboratory.
Unexpectedly, the building's concrete strength also met the standard.
The accident investigation was once deadlocked.
Concrete compressive strength test
Investigators who lost their clues decided to re-clip the information at hand.
When calculating the building's architectural drawings and bearing capacity, they found some clues.
According to calculations, the building needs columns with a diameter of 80cm, including 16 steel bars.
can be measured on site to show that the diameter of the column has been reduced to 60cm and there are only 8 steel bars.
This causes the overall strength of in the building to be reduced by nearly half .
But this is not the main reason for the collapse of Sanfeng Department Store.
buildings have security reserves when designing, that is, design requires that the bearing capacity of is greater than the bearing capacity of actually requires.
Even if the intensity is greatly reduced, the building can remain intact without encountering special circumstances.
This is also the reason why there have been no major problems in the building since its construction 6 years ago.
As the investigation deepened, the investigators discovered another building defect at the scene.
This time, the steel bars in the concrete floor slab were placed in the wrong position , and changed from 5cm away from the surface to 10cm away from the surface. The five centimeter changes of
are quite a bit important, which is equivalent to directly weakening the thickness of the floor slab.
, and Sanfeng Department Store adopts a beamless floor structure*, with only the floor slabs and columns bearing the load.
This error reduces the strength of the floor slab by 20%.
*Note: There is no beam under the floor slab, it is directly supported by columns. The instability of a column can easily lead to building chain damage, and the requirements for design and construction are quite high.
various signs indicate that the management of Sanfeng Group has major negligence in , and they all survived the disaster.
So the investigators turned their attention to them.
Sanfeng Group Chairman Li Yu (first right)
Through inquiry, investigators found that the building was originally designed with only four floors and was intended to be used as an office building.
After the original contractor set the foundation, Sanfeng Group put forward the requirement to significantly change the design of by .
Not only do they want to convert the office building into a shopping mall, but they also add an additional floor to it. This change in
has resulted in many load-bearing columns of being cancelled to make room for installation of escalators.
The contractor did not agree to the modification, and the president Li Li simply fired them and asked his own construction company to take over the construction.
Li Yongzhou also revealed that the fifth floor of the mall originally planned to be a skating rink, but later it was changed to 8 traditional restaurants.
Koreans have the habit of sitting on the floor, so all restaurants need to install heating equipment under under .
The extra equipment adds the weight of the fifth floor floor, putting very heavy pressure on the building structure that originally had only four floors.
Another culprit for serious overload in the building is the air conditioning equipment on the roof.
The total weight of three large water-cooled air conditioners is 29 tons, and after filling with water, it can reach 87 tons. This is much beyond the design standard .
After investigation, the most critical factor in the accident also came from these three air conditioners.
Two years ago, three air conditioners were moved to their locations due to nearby residents complaining about the noise of the air conditioner.
This kind of large equipment should have been lifted to a new position with a crane , but Sanfeng Group lazily placed the air conditioner on the wheels and dragged them directly on the roof.
It turns out that this is a very bad decision.
dozens of tons of air conditioners were dragged to the other side of the roof, causing irreversible damage to the building structure . There were cracks of varying degrees where the air conditioner passed by, and the columns of Chunyuan Restaurant were particularly damaged.
In the past two years, the vibration caused by turning on the air conditioner will cause the cracks to spread .
When there are enough cracks around the column, the floor of Chunyuan Restaurant can no longer bear it.
After the first floor slab fell, the collapse quickly spread to the entire floor.
The upper floor slab fell to the lower floor and caused the lower floor to collapse, and the Sanfeng Department Store was razed to the ground.
On the 17th day after the accident, heavy machinery is cleaning up the building wreckage.
At this time, the focus of the excavation work has changed from survivors to to find the remains .
Everyone has no hope for the survival of the victims.
At this moment, the on-site personnel found a hole behind a concrete slab.
In the hole they were surprised to find a 19-year-old salesperson Park Seung Hyun .
After being trapped in the dark for 377 hours , she miraculously survived, and there was nothing serious about it except severe dehydration.
This news spread throughout the country as soon as it was reported, but Park Seung Hyun is also the last person to be rescued from the ruins of alive.
502 Life was taken away by this disaster, people's sorrow turned into anger, and months of demonstrations began.
They can't understand how such a casual engineering project passed the review.
Follow-up investigation shows that several government officials are suspected of accepting bribes during the construction of Sanfeng Department Store, and there are also extensive embezzlement and fraud within Sanfeng Group.
On December 27, 1995, the chairman of Sanfeng Group, Li Li , was sentenced to , 510 years and 6 months in prison for negligent death, and his son Li Hanxiang, , was also sentenced to 7 years in prison for corruption and other charges.
A large number of stakeholders were prosecuted, and a total of 21 people were found guilty, of which 12 were government officials.
During the explosive growth of South Korea's economy in the 1980s, monetary interests overwhelmed everything .
Commercial Group pursues profits and insists on doing its own thing, while government officials turn a blind eye to the chaos in the project.
is even on the verge of crisis, and the dazed capitalists still have to greed for profit for a long time, and bet on the safety of more than a thousand people.
accidents will indeed make people learn from their lessons, but 's greedy tragedy won't go far.
's blind pursuit of interests is the best breeding ground for these disasters.
