Sampoong Department Store collapse

Following the selection of Seoul as host city of the 1988 Summer Olympics, there was a large development boom in the Seoul Capital Area. As local law did not allow foreign contractors to sign contracts for projects in Seoul at the time, almost all buildings were being erected by South Korean companies, which typically built the structures quickly and with a low quality because of the large number of projects assigned to them. The Sampoong Group began construction of the Sampoong Department Store in 1987 over a tract of land in the Seocho District previously used as a landfill. The building's plans originally called for a residential apartment building with four floors to be built by Woosung Construction. Woosung refused to carry out these changes due to serious structural concerns. In response, Lee Joon fired them and used his own company to complete the store's construction instead. The building was completed in late 1989, and the department store opened to the public on July 7, 1990, attracting an estimated 40,000 people per day during the building's five years of existence. The store consisted of north and south wings connected by an atrium. The completed building was a flat-slab structure without crossbeams or a steel skeleton, which effectively meant that there was no way to transfer the load across the floors. To maximise the floor space, Lee Joon ordered that the diameter of the floor columns be reduced to , instead of the minimum of in the original blueprint that was required for the building to stand safely. In addition, the spacing between columns was increased to ; with fewer columns, each one had to support a larger load than originally designed. The fifth-story restaurant floor had a built-in heating system known as an ondol, with hot water pipes passing through a concrete base. The weight and thickness of the ondol further increased the load on the structure. Three air conditioning units, weighing 15 tonnes each when empty, were installed on the roof. These units generated high noise levels when operating, leading to complaints from adjacent property owners; in an attempt to remedy the situation, they were dragged across the roof to a new location in 1993, resulting in cracking. The units were moved over column 5E, where the most visible cracks in the fifth floor were seen before the collapse. The cracks worsened because the columns supporting the fifth floor were not aligned with the ones supporting lower floors, thus causing the load of the fifth floor to be transferred through the slab. ==Timeline of events==

Collapse In April 1995, cracks began to appear in the ceiling of the fifth floor in the south wing, but the only response by Lee Joon and staff management was to move merchandise and stores from the top floor to the basement. On the morning of June 29, the number of cracks in the area increased dramatically, prompting store management to close parts of the top floor. However, the management failed to shut the building down or issue formal evacuation orders, At about 5:00 p.m., KST (UTC+9:00), as the fifth floor ceiling began to sink, store workers finally closed off all customer access to the fifth floor. Fifty-seven minutes before the collapse, the store was packed with hundreds of shoppers, but still, Lee Joon did not close the store or attempt any repairs. At about 5:52 p.m., cracking sounds could be heard and workers began to sound alarms and evacuate the building, but it was too late. The roof gave way and the air conditioning units crashed onto the overloaded fifth floor which then gave way. In less than twenty seconds, the building's main columns (which had been weakened by the installation of the escalators) failed, followed by all the columns in the south wing. The store's south wing, excepting the very southernmost part, then collapsed completely into the basement trapping more than 1,500 people inside. 502 people died and 937 were injured. The disaster resulted in property damage totaling about ₩270 billion (about US$206 million). Rescue efforts Rescue crews were on the scene within minutes of the disaster, with cranes and other heavy equipment being brought in the next day. However, Seoul's mayor, Choi Pyong-yol, announced the rescue would be called off due to concerns that the unstable remains of the store would collapse. After massive protests, especially from friends and relatives of those still missing, Choi and officials agreed to continue looking for survivors, with the remains of the store being steadied by guy cables. At one point, Korea Telecom was transmitting a signal every half hour, designed to trigger cellphones or pagers that trapped survivors might be carrying. After nearly a week, the focus was on removing the debris, but construction crews continued to search for victims. Two weeks after the collapse, city officials concluded that anybody who was still in the building must have already died; therefore, further efforts would be made only towards "recovery", not "rescue". Despite the sweltering heat, some who were not rescued in the first few days avoided dehydration by drinking rainwater. The last to be rescued, 19-year-old store clerk Park Seung-hyun (), was pulled from the wreckage 17 days after the collapse with a few scratches; 18-year-old Yoo Ji-hwan was pulled out after nearly twelve days; and a man rescued after nine days reported that other trapped survivors had drowned from the rain and from the water used for fire suppression. == Casualties ==

The collapse killed 502 people and injured about 937 people. About 1,500 people were trapped inside the structure. Rescue attempts lasted over the course of many days leading to the rescue of a few survivors, including two that were pulled from the wreckage after a week. == Investigation ==

The investigation of the collapse was headed by Professor Chung Lan () of Dankook University's engineering school. It was also widely feared that there had been a terrorist attack, with North Korea as the prime suspect. However, the fact the building collapsed downward, with little debris thrown outward, ruled out a significant explosion, according to South Korean and American experts. Once the investigation focused on structural failure, it was initially believed the building's poorly laid foundation and the unstable ground that it was built on, both led to the failure. Investigation of the rubble revealed that a substandard concrete mix of cement and seawater and poorly reinforced concrete was used for the ceilings and walls. Further investigation revealed that the building was built with incorrect application of a technique called "flat slab construction". Reinforced concrete buildings are often built by 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 must be reinforced in order to carry the load; if the columns are too narrow, they can punch through the slab. Examination of the building showed the concrete columns installed were only in diameter, below the required shown in the plans. The number of steel reinforcement bars embedded into the concrete was 8, not the required 16, which gave the building only half its needed strength. Steel reinforcements intended to strengthen the concrete floor were placed from the top instead of , decreasing the structure's strength by about another 20%. Fire shields were installed around all escalators to prevent the spread of fire from floor to floor, but to install them, the support columns were cut, further reducing their diameter. The reduced diameter concentrated the load on a smaller area of the slab, leading to an eventual puncturing of it. Those factors, along with the addition of a fifth floor including restaurants and heavy restaurant equipment, all contributed to the building's eventual failure. The final design had less than half of the required strength but despite this managed to stand for almost five years. Investigators finally pinpointed the direct cause of the collapse, known as the "trigger" or tipping point, in the building's history. It was revealed that two years before the collapse, the building's three rooftop air-conditioning units had been moved because of noise complaints from neighbors on the east side of the building. The building's managers admitted noticing cracks in the roof during the move, but instead of lifting them with a crane, the units were put on rollers and dragged across the roof, further destabilizing the surface by each unit's immense weight. Cracks formed in the roof slabs and the main support columns were forced downward. Column 5E took a direct hit, forming cracks at the position connected to the fifth-floor restaurants. According to survivor accounts, each time the air conditioners were switched on, the vibrations radiated through the cracks, reaching the supporting columns and widening the cracks, over the course of two years. On the day of the collapse, although the units were shut off, it was too late: the structure had suffered irreversible damage, and the fifth floor slab around column 5E finally gave way. == Legal ==

visits the site of the collapse Trial and prison sentence During his interrogation with Professor Chung, Lee Joon sparked further controversy by saying that his main concern was that the collapse of the store not only harmed the customers, but also inflicted great financial damage to his company. On December 27, 1995, Lee Joon was found guilty of criminal negligence and received a prison sentence of ten and a half years. Prosecutors originally asked for Lee Joon to be sentenced to twenty years, but was reduced to seven and a half years on appeal. Lee Joon died on October 4, 2003, months after his release from prison, of complications from diabetes, high blood pressure and kidney disease. Lee Joon's son and the store's CEO, Lee Han-sang, Following his release from prison in 2002, Lee Han-sang worked as an evangelist in Mongolia. Other participating officials, including a former chief administrator of the Seocho district, were also jailed. Other parties sentenced included a number of the store's executives and the company responsible for completing the building. Compensation At first, families of the victims were asking for an average of $361,000 each. However, the City of Seoul, representing the store's owner, offered to pay $220,000 for each victim, arguing that he could not afford to pay more. Two months after the collapse, Lee Joon and Lee Han-sang submitted a jointly signed memo to Seoul, offering their entire wealth to compensate the families of the victims. As a result, the Sampoong Group ceased to exist. The settlement involved 3,293 cases, totaling ₩375.8 billion (about $300 million). Payouts were complete by 2003. == Reaction ==

The initial reaction of the disaster was an enormous public outrage that led to months of public demonstrations on the streets of Seoul. The disaster led to skepticism and fears regarding safety standards on other engineering projects undertaken as South Korea had experienced an economic boom during the 1980s, and it resulted in a review of South Korean safety regulations; the disaster also revealed the level of corruption and greed among city officials, who were willing to accept bribes with little regard for public safety. == Legacy ==

The remains of the store were demolished shortly after the collapse and the recovery operations; the site remained vacant until 2000. The families of the victims requested that a memorial be built on the site, but it was opposed by the Seochu District government, forcing the Seoul Metropolitan Government to mediate the dispute. In a controversial move, the memorial was built elsewhere and the land sold off to a private developer. The site of the collapse is now home to a luxury apartment complex, Acrovista, the construction of which began in 2001 and was completed in 2004. The impeached former South Korean president Yoon Suk Yeol was a resident of this apartment until moving to the Presidential Residence six months after assuming office. Memorials The Yangjae Citizen's Forest has a sculpture made in memory of the collapse. The marble memorial was designed by Ewha Womans University professor and sculptor Kim Bong-gu, and funded by the Sampoong Group as compensation to the victims. ==Cultural references==

Documentary • Blueprint for Disaster – "The Sampoong Collapse" (2004) • Seconds from Disaster – "Sampoong Department Store Collapse" (2006) Film • Judgement (1999) • Traces of Love (2006) Television • Chocolate (2019) • When My Love Blooms (2020) ==See also==