Sampoong department store collapse

The Sampoong Department Store (삼풍백화점; 三豊百貨店) collapse was a structural failure that occurred on June 29, 1995 in the Seocho-gu district of Seoul, South Korea. The collapse is the largest peacetime disaster in South Korean history – 501 people were killed and 937 injured. It was a direct result of the deliberate use of substandard construction materials, remarkably poor engineering practises, and governmental corruption.

Building overview

The Sampoong Group began construction of the Sampoong Department Store in 1987 over a tract of land previously used as a landfill. Originally designed as an office building with four floors, Lee Joon, the future chairman of the building, redesigned the building as a large department store later on during its construction. This involved cutting away a number of support columns in order to permit the installation of escalators. When the initial contractors refused to carry out these changes, Lee fired them and hired his own building company to construct the building.

The building was completed in late 1989, and the Sampoong Department Store opened to the public on July 7, 1990, attracting an estimated 40,000 people per day during the building's five years in service. The store consisted of a north wing and south wing, connected by an atrium.

Later on, a fifth floor was added to the four-floor building, which was first planned to be a skating rink; the skating rink was added due to regulations that stopped the whole building from being used as a department store. Lee changed the original plan for the fifth floor to include eight restaurants. When a construction company tasked to complete the extension advised that the structure would not support another floor, they were fired, before another company finished the job. The restaurant floor also had a heated concrete base with hot water pipes going through it, as patrons sit on the ground of traditional Korean restaurants, which added a large extra load as a result of increasing the thickness of the concrete slab. In addition, the building's air conditioning unit was now installed on the roof, creating a load of four times the design limit.

Collapse

In April, 1995, cracks began to appear in the ceiling of the south wing's fifth floor. During this period, the only response carried out by Lee and his management involved moving merchandise and stores from the top floor to the basement. The store management failed to shut the building down or issue formal evacuation orders, as the number of customers in the building was unusually high, and the store was not intending to lose potential revenue for that day. However, the executives themselves had left the premises as a precaution.

On the morning of June 29, the number of cracks in the area increased dramatically, prompting managers to close the top floor and shut the air conditioning off. Civil engineering experts were also invited to inspect the structure, with a cursory check revealing that the building was at risk of collapse; The National Geographic documentary series Seconds From Disaster indicates that the facility's manager was examining the slab in one of the restaurants on the fifth floor, eight hours before the collapse, when, unknowingly, vibrations from air conditioning were radiating through the cracks in the concrete columns and the floor opened up.

Five hours before the collapse, the first of several loud bangs were emitted from the top floors, as the vibrations in the air conditioning caused the cracks in the slabs to widen further. Amid customer reports of the vibrations, the air conditioning was turned off, but the cracks in the floors had already widened to 10cm.

At about 5:00 p.m. Korea Standard Time (UTC+9:00), the fourth floor ceiling began to sink, resulting in store workers blocking customer access to the fourth floor. According to Seconds From Disaster, the store was packed with shoppers 52 minutes before the collapse, but the owner did not close the store or carry out repairs at the time. When the building started to produce cracking sounds at about 5:50 p.m., workers began to sound alarm bells and evacuate customers.

Around 6:05 p.m., the roof gave way, and the air conditioning unit crashed through into the already-overloaded fifth floor (Seconds From Disaster indicates that the fifth floor slab and roof were the first to collapse, causing the air conditioning units to fall through the structure). The main columns, weakened to allow the insertion of the escalators, collapsed in turn, and the building's south wing pancaked into the basement. Within 20 seconds, all of the building's columns gave way, trapping more than 1500 people and killing 500.

The disaster resulted in about 270 billion (approximately US$216 million) worth of property damage.

Aftermath

Rescue and Recovery

Rescue crews were on the scene within minutes of the disaster, with cranes and other heavy equipment being brought in the next day. However, authorities announced that they would call off the rescue, due to the danger that the unstable remains of the store would come down, and many of the rescuers were at risk. Massive protests, especially from friends and relatives of those still missing, compelled officials to continue looking for survivors, with the remains of the store being steadied by guide cables. After nearly a week, the focus was on removing the debris, though construction crews were careful to check for victims.

Two days after the collapse, some officials said that anybody who was still in the building must have already died; therefore, further efforts would be made only towards "recovery" and not "rescue". This conflicts with other peoples' experience in different countries, which is that humans can survive much longer than it is commonly thought. Despite the sweltering heat, those who were not rescued in the immediate few days were able to avoid dehydration by drinking rainwater. In fact, this was demonstrated rather dramatically when the last survivor, 19-year-old Park Seung Hyun (박승현; 朴勝賢), was pulled from the wreckage 16 days after the collapse, fortunately suffering only a few scratches.

Investigation

Shortly after the collapse, it was immediately thought that leaking gas caused the collapse, due to the fact that two gas explosions had occurred elsewhere in the city earlier in the year. However, the only fires amid the rubble was the burning gasoline from the crushed cars in the underground garage, whereas a gas explosion would have been a massive inferno. There were also fears that the collapse was the result of a terrorist attack, including North Korea as a prime suspect, perhaps similar to the Oklahoma City bombing in the USA. However, the fact that the building collapsed straight down instead of sideways ruled out the second possibility.

It was also initially thought that the building's poorly laid foundation and the fact that it was built on unstable ground led to the failure. Investigation of the rubble revealed that the building was constructed with a substandard concrete mix (of cement and sea water) and poorly reinforced concrete on the ceilings and walls.

Further investigation revealed that the building was built using a technique called "flat slab construction". Reinforced concrete buildings are often built using columns and beams, with the floor slab supported over the full length of the beams. "Flat slab construction" does not use beams, but supports the floor slab directly on the columns. The area of floor around the columns has to be specially reinforced to carry the load; even then, if the columns are too small they can punch through the slab. However, blueprints of the building showed that the concrete columns were only 60cm in diameter, below the required 80cm. Worse still, the number of bars reinforcing the concrete was 8, half of the required 16, giving the building only half the strength needed. Steel slabs that strengthen the floor were also unsatisfactory: They were 10cm from the top of the floor when they should have been 5cm, decreasing the structure's strength by about another 20%.

The final change that brought the building down was, ironically, installation of a safety feature. Fire shields were installed around all escalators to prevent the spreading of fire from floor to floor, but to install them, the builders cut into the support columns, reducing their size even further. The columns were no longer able to properly hold up the concrete slab, and would eventually punch shear through the ceiling, whereby the column would punch a hole through the ceiling, instead of supporting it.

These factors, along with the aforementioned addition of fifth floor restaurants and restaurant equipment, contributed collectively to the building's eventual collapse. While the original design of the building would have been over twice as strong as needed to stand up, the flawed structure still managed to hold up for five years. The investigators then turned to find the direct cause of the collapse, known as the "trigger" or tipping point, and they discovered it in the building history.

It was revealed that the building's three roof-top air conditioning units were moved in 1993 due to noise complaints from neighbours on the east side of the building. The building's managers confirmed that they were moved and cracks were on the roof, but instead of lifting them with a crane, the units were put on rollers and dragged across the roof, making the roof more unstable. Cracks formed in the roof slabs and the main support columns were forced downwards; column "5e" took a direct hit and cracks formed in the position connected to the fifth floor restaurants. Another issue attributed to air conditioning units came from survivor accounts of the building vibrating. Over the period of two years, vibrations radiated through the cracks to the supporting columns each time the air conditioners were switched on, worsening the cracks. On the day of the collapse, even though the units were shut off, it was too late by then as it had done too much damage and column "5e" gave way.

Trial

Lee was charged for negligence and received a prison sentence of ten and a half years. His son, Lee Han-Sang, the store's president, faced seven years for the same charge.[1] City officials dispatched to oversee the construction of the building were also found to have been bribed into concealing the illegal changes and poor construction of the building. As a result, the participating officials, including a former chief administrator of the Seocho-gu district, were also jailed for their part. Other parties sentenced included a number of Sampoong Department Store executives and the building company responsible for completing the building.

General reaction and nationwide building review

The disaster led to skepticism and fears regarding safety standards on other engineering projects undertaken as South Korea experienced an economic boom during the 1980s and 1990s, and resulted in a review of South Korean safety regulations; the incident also revealed the level of corruption among city officials, who were willing to accept payoffs with little regard to public safety.

Popular culture

The Sampoong Department Store collapse was depicted in the 2006 film, Traces of Love.

See also

Gangi department store collapse

Seongsu Bridge

References

1. ^ "Korean store owner, son sentenced for role in collapse", CNN.com, December 27, 1995. Retrieved on 2006-06-01. 

External links

Hangul (한글) or Chosŏn'gŭl (조선글) [2]

ISO 15924 Hang

Note
..... Click the link for more information.
Origins
Traditional Chinese
Variant characters
Simplified Chinese
Simplified Chinese (2nd-round)
Traditional/Simplified (debate)
Kanji
- Man'yōgana
Hanja
- Idu
Han Tu
- Chữ Nm

..... Click the link for more information.
Structural failure refers to loss of the load-carrying capacity of a component or member within a structure or of the structure itself. Structural failure is initiated when the material is stressed to its strength limit, thus causing fracture or excessive deformations.
..... Click the link for more information.
June 29 is the 1st day of the year (2nd in leap years) in the Gregorian calendar. There are 0 days remaining.

Events

  • 512 - A solar eclipse is recorded by a monastic chronicler in Ireland.

..... Click the link for more information.
19th century - 20th century - 21st century
1960s  1970s  1980s  - 1990s -  2000s  2010s  2020s
1992 1993 1994 - 1995 - 1996 1997 1998

Year 1995 (MCMXCV
..... Click the link for more information.
Seocho-gu is a gu of Seoul, South Korea. It is a ritzy, upper-class ward located in the southeast of the city. Seocho-gu is home to the majority of Seoul's French population, as well as many other foreigners including diplomats.
..... Click the link for more information.
Seoul (서울) listen   [sʌ.
..... Click the link for more information.
Motto
홍익인간(弘益人間) 널리 인간을 이롭게 하?
Anthem
Aegukga (애국가; 愛國歌)
..... Click the link for more information.
landfill, also known as a dump or tip (and historically as a midden), is a site for the disposal of waste materials by burial and is the oldest form of waste treatment.
..... Click the link for more information.
department store is a retail establishment which specializes in selling a wide range of products without a single predominant merchandise line. Department stores usually sell products including apparel, furniture, appliances, electronics, and additionally select other lines of
..... Click the link for more information.
escalator is a conveyor transport device for transporting people, consisting of individual, linked steps that move up or down on tracks, which keep the treads horizontal.
..... Click the link for more information.
A general contractor is an organization or individual that contracts with another organization or individual (the owner) for the construction of a building, road or any other execution of work or facility.
..... Click the link for more information.
7th July, July 7th, and 7/7 (pronounced "Seven-seven") have been widely used in the Western media as a shorthand for the 7 July 2005 bombings on London's transport system.
..... Click the link for more information.
20th century - 21st century
1960s  1970s  1980s  - 1990s -  2000s  2010s  2020s
1987 1988 1989 - 1990 - 1991 1992 1993

Year 1990 (MCMXC) was a common year starting on Monday (link displays the 1990 Gregorian calendar).
..... Click the link for more information.
atrium (plural atria) is a large open space, often several stories high and having a glazed roof and/or large windows, often situated within an office building and usually located immediately beyond the main entrance doors.
..... Click the link for more information.
Concrete is a construction material that consists of cement (commonly Portland cement) as well as other cementitious materials such as fly ash and slag cement, aggregate (generally a coarse aggregate such as gravel limestone or granite, plus a fine aggregate such as sand or
..... Click the link for more information.
Concrete slab is a common structural element of modern buildings. Horizontal slabs of steel reinforced concrete, typically between 10 and 50 centimetres thick, are most often used to construct floors and ceilings, while thinner slabs are also used for exterior paving.
..... Click the link for more information.
Seconds From Disaster was a documentary television series that investigates the worst and several natural disasters in modern history, and analyses the causes and events that led up to each disaster.
..... Click the link for more information.
South Korean won
대한민국 원 (Hangul)
大韓民國 원1 (Hanja)

..... Click the link for more information.
United States dollar
dólar estadounidense (Spanish)
dólar amerikanu (Tetum)
dólar americano

..... Click the link for more information.
Property damage is damage or destruction done to public or private property, caused either by a person who is not its owner or by natural phenomena. Property damage caused by persons is generally categorized by its cause: neglect (including oversight and human error), and
..... Click the link for more information.
Oklahoma City bombing

Damage to the Murrah building before cleanup began.
Location Oklahoma City, Oklahoma, USA

Target(s) Alfred P.
..... Click the link for more information.
A foundation is a structure that transfers loads to the ground. Foundations are generally broken into two categories: shallow foundations and deep foundations.

Shallow foundations

Main article: Shallow foundation

..... Click the link for more information.
In the most general sense of the word, cement is a binder, a substance which sets and hardens independently, and can bind other materials together. The name "cement" goes back to the Romans who used the term "opus caementitium" to describe masonry which resembled concrete and was
..... Click the link for more information.
Seawater is water from a sea or ocean. On average, seawater in the world's oceans has a salinity of ~3.5%, or 35 parts per thousand. This means that every 1 kg of seawater has approximately 35 grams of dissolved salts (mostly, but not entirely, the ions of sodium chloride: Na
..... Click the link for more information.
Reinforced concrete, also called ferroconcrete in some countries, is concrete in which reinforcement bars ("rebars") or fibers have been incorporated to strengthen a material that would otherwise be brittle.
..... Click the link for more information.
Tort law II
Part of the common law series
Negligent torts
Negligence  · Negligent hiring
Negligent entrustment  · Malpractice
Negligent infliction of emotional distress
Doctrines affecting liability
..... Click the link for more information.
prison, penitentiary, or correctional facility is a place in which individuals are physically confined or interned and usually deprived of a range of personal freedoms.
..... Click the link for more information.


In law, a sentence forms the final act of a judge-ruled process, and also the symbolic principal act connected to his function.
..... Click the link for more information.
President is a title held by many leaders of organizations, companies, trade unions, universities, and countries. Etymologically, a "president" is one who presides , who sits in leadership (from Latin prae- "before" + sedere "to sit"; giving the term
..... Click the link for more information.


This article is copied from an article on Wikipedia.org - the free encyclopedia created and edited by online user community. The text was not checked or edited by anyone on our staff. Although the vast majority of the wikipedia encyclopedia articles provide accurate and timely information please do not assume the accuracy of any particular article. This article is distributed under the terms of GNU Free Documentation License.