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The Victoria Hall Disaster of 1883

Why that happened

You know those handles on doors that are long (across the door’s entire width) and you have to push them down to open them? Those are called “push bars” and  were invented shortly after the Victoria Hall Disaster of 1883. On the 16th of June, 1883, there was a variety show held at the Victoria Hall by Mr and Mrs Fay who were travelling entertainers. The hall was located in Sunderland, England but was destroyed during the bombing raids in World War 2. 

The disaster itself happened like this: The performers announced that there would be a treat for 20 kids who had lucky ticket numbers. Now, what happened was, the kids from the top galleys surged downstairs towards the stage. What resulted was a mass of kids being essentially falling into this narrow corridor that made up the stairway. They couldn’t open the doors because they had been bolted to only allow one kid through at a time. The reason for bolting the doors like this was to ensure orderly ticket checking. The kids in the front were crushed by the pressure created by the kids in the back. By the time the adults realised what was happening, they had to scramble to be able to do anything about it. 

They could not open the doors, because it was bolted on the kids’ side, and therefore they had to pull one kid through at a time while someone had to run around and redirect the kids away. 600 kids were saved, but 183, who were in the front, got crushed. This lead to the invention of the Push Bar door handle, to prevent incidents like this, and there was an increase in the amount of safety doors that a theatre or concert hall was mandated to have. 

The push bar is designed to prevent crowd crushing in narrow corridors or at the entrance of convenience stores. You can see how this would have saved those kids lives but unfortunately, some of the best safety precautions are only created after they were needed. This is an unfortunate reality of engineering and architecture, some lessons have to be learned the hard way.

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The Sampoong Department Store Collapse.

Why that happened:

The construction of the Sampoong department store was an undertaking funded by Lee Joon, of the Sampoong Group. The site which had previously been a landfill, had been slated to become a four story apartment complex. Lee Joon later changed the plans to include a fifth floor, and for it to become a shopping centre basically.

The original layout was then changed, and a lot of the interior support columns were removed to put escalators in. See, when the building was originally built, the columns themselves had a safety factor of 2, meaning, they could support 2 times the weight they were at present, but, when the inner columns were removed, and fifth floor was added, the pressure on the columns increased.

The columns also weren't big enough to support the weight properly. It was recommended that these columns be 80-90 cm in diameter, but in an attempt to maximize on floor space so more merchandise could be fit into stores, the columns' width was reduced to 60 cm.

This is bad, since the entire building was a flat slab structure. Basically, its supposed to be reinforced cement slabs (that would be the floor/ceiling on each story) that were held up by thick columns. If the the columns are two narrow, the pressure could actually forced the column to puncture through the floor. 

It should be noted the first company that Lee Joon had hired to build the store, Woosung Construction, outright refused to make these changes, so Lee fired them and used a company he created to build it instead. 

Another issue, to reduce on costs, only 8 steel bars were imbedded into the concrete instead of the required 16. Now, the slabs are made from reinforced concrete, the reinforcement comes from those steel bars. The steel bars will prevent the concrete was giving way or tearing. The steel bars were also, for some reason, placed 10 cm away from the top of the slab, as opposed to 5 cm, which means they were almost effectively useless.

But the crowning problem, was the fifth floor. Remember how the original plans only had four? Well the fifth was added later, and added sloppily. The columns supporting the roof of the fifth floor, were not aligned with the columns supporting the rest of the floors. The result is the weight of the roof is being distributed down the colum, across the slab, and the down into the lower floors' columns. Remember when I said the slabs were bad at supporting weight?

Now, Lee could have gotten away with this, but, he decided to make the fifth floor the heaviest. There were zoning regulations in that district that stipulated that building had to be mixed purpose, and could not just have shops. To circumvent this Lee had planned to put an ice rink on the fifth floor, but plans later changed to restauraunts instead. Now restaurants have heavy equipment themselves.

On top of that, hot water pipes were installed through the floor for heating purposes. Floor heating was a common in Korea at the time, and the pipes were very heavy, and thick, meaning the weight and thickness of the fifth floor slab was also greatly increased.

The final nail in the coffin, was the installment of three 15 tonne air conditioning units on the roof. The buildings columns now had to support 4x the weight they were built to able to support.

Noise complaints from residents around the building resulted in them having to move AC units. Instead of sensibly using a crane, the ACs were just put on rollers and dragged across the roof. Because thats a good idea. This weakened the roof quite a bit. The ACs were placed over column 5E, which had already begun to show cracks. Workers would later say that whenever the AC was turned on, cracks would widen in the columns due to the vibrations being sent through them. The cracks had actually already begun to show in april year, in response, Lee simply had merchandise moved from the top floor down to the basement.

On the day of the collapse, (29 June 1995)  massive cracks appeared in the roof. A civil engineer was called in to inspect the site, and it was determined that the building was at high risk of collapse.  An emergency meeting was held, where the board tried to persuade Lee to close down the store but he didnt because he did not want to lose out on any profits. All the executives left as a precaution, but the store remained in operation. Workers started reporting the vibrations they could at this point hear on the top floor and the ACs were shut off, but by this point it was too late. At 5:52 pm workers decided to evacuate the building after hearing cracks from the top floor, but then the top floor caved in at 5:55pm. The ACs units finally fell through the roof, and the rest of the floors pancaked down to the basement floor. This collapse took 20 seconds. 502 people were killed, and around 1500 were trapped inside.

Rescue efforts were begun shortly afterwards, even though the mayor had at first wanted to prevent this out of fear that rescue workers would also be hurt/killed.

After 2 days, it was thought that most of the people who were trapped had perished, but recovery teams kept carefully searching though the rubble and continued to find people, most of whom had survived by drinking rainwater. (Unfortunately, many who trapped in the lower floors drowned due to the fire suppression systems switched on and releasing water. The last person to be pulled out was Park Seung-hyun (19), who was saved 17 days after the collapse.

Lee ended up getting 10 and a half years in prison, on a charge of criminal negligence, and he had to give his entire family wealth to the victims, and the Sampoong group was disbanded. 

Now, in short, poor construction is the technical reason for the disaster, but what would drive someone to do this? Well, Lee Joon himself was obviously just a greedy man who wanted to cut as many corners as possible, I mean he refused to even close the sore when he was being told “Listen, this is going to collapse” out of fear of loosing revenue. Another thing to understand that capitalism was at a boom in Korea at the time, and Korea had a law against outsourcing construction contracts, so a lot of building companies built stuff really quickly (which means of cheaply and shoddily) to get through all the orders they were getting, and also with added pressure of the Olympics. 

But, it is clear from this event, how one man’s greed can cause a huge catastrophe like this. 

TL;DR: Bad, cheap architecture, building not built properly, top floor too heavy and eventually fell into lower floors. Guy who built the place was a cheapskate and due to corner cutting the building collapsed, and he refused to evacuate the building when it was about to collapse and 500 people died because of it.