- hace 3 horas
Hotel New World, a one-star budget hotel located in Singapore's Little India district, collapses due to growing microcracks in the failing structural columns. The cracks were caused by a miscalculation of the building's structural load by the structural engineer. After a seven-day rescue operation, 17 people are saved, but 33 perish.
Categoría
📺
TVTranscripción
00:01Singapore, famed throughout Asia for its order and calm efficiency.
00:07Then suddenly, one Saturday morning, disaster stops the entire country in its tracks.
00:15A six-story hotel crashes to the ground in under 60 seconds.
00:2133 people die and 17 more are buried alive,
00:25trapped beneath thousands of tons of steel, glass and concrete.
00:30It's the worst collapse in the country's history and it leaves investigators baffled.
00:36Now, using advanced computer simulations, we reveal exactly what caused the tragedy.
00:43Disasters don't just happen, they're a chain of critical events.
00:48Unravel the clues and count down those final seconds from disasters.
01:03Asia, Singapore, over 4 million people live crammed in a country the size of New York City.
01:11It's a dynamic, vibrant place that attracts people from all over the region and beyond,
01:17striving to make a better life for themselves in this English-speaking island of opportunity.
01:25Downtown, tower blocks soar into the sky as architects struggle to maximize the limited space.
01:34Much of it, land reclaimed from swamp and sea.
01:41Even below ground, the city is teeming with activity as Singapore expands at breathtaking pace.
01:52Giant tunnels aboard by teams of engineers from all over the world, working on a new subway system that will
01:58connect the high-rise area with older and less prosperous districts like this one, Little India.
02:05Six kilometers from downtown, this area is home to the manual laborers who support the booming economy.
02:12Here on Owen Road stands the Hotel New World, built in 1971.
02:17The building is unremarkable.
02:20Thirty-six reinforced concrete columns supporting six concrete floors.
02:26There's a car park in the basement.
02:28The local branch of a bank takes up the ground floor.
02:31Above that is a popular nightclub.
02:34And a budget hotel occupies the rest of the building.
02:37As is usual in this hot climate, air conditioning units and water tanks are installed on the roof.
02:45At over 24 meters, it's small by Singapore standards, but one of the tallest buildings in Little India.
02:53The building has led an untroubled life, apart from one serious incident.
02:59In 1975, when a gas leak poisoned 35 people.
03:08Everybody made a full recovery.
03:10And the building was given a clean bill of health.
03:15March 14th, 1986, 11 years later.
03:22It's a Friday night, and as usual, Madame Lily Teo, the nightclub hostess, sets up the first-floor bar,
03:28in preparation for a busy evening, expecting the usual mix of businessmen and couples who visit her club.
03:49She's startled to see that a column on the dance floor has cracked.
03:57The time is 7pm.
04:00She decides to inform the building's owner.
04:04Shortly afterwards, with the nightclub now open, a couple of workmen start repairing the damage.
04:11No one pays much attention to them.
04:17By 9.15pm, the club is in full swing.
04:21In the staff dressing room, one of the girls checks her makeup.
04:37In Singapore, like most countries around the world, a broken mirror is a symbol of bad luck.
04:47But it's the end of the working week, and everyone in the nightclub is too busy having a good time
04:51to worry about silly superstitions.
04:59The next morning, Saturday, March 15th.
05:058am.
05:11Xiong Cheng Guan, assistant manager of the ground floor bank, walks through the park with his childhood sweetheart.
05:18They were married three months ago, but he's been working so hard, they haven't had time for their honeymoon yet.
05:27We were happily married, and we actually planned a trip to Australia and New Zealand.
05:32As Xiong leaves for work, he says goodbye to his wife, Leong Sisi, knowing it's a big day for her.
05:39She's taking an important exam.
05:43I was having my final exam for a diploma.
05:46Chong and I had planned to meet in the afternoon.
05:49As it's a Saturday, the bank will close at lunchtime, and the couple are planning on spending the rest of
05:54the day walking hand in hand through Singapore's busy streets.
05:58I was looking forward to Saturday afternoon, after work, and then usually we will go out.
06:0617 people work in the bank.
06:09It's a close, friendly team.
06:12As is common in Singapore, they take great pride in providing their customers with efficient service.
06:2121-year-old Christina Foer has been working at the bank for just three months.
06:28This is my first job in the bank, and I enjoy it very much.
06:33Christina has never been up to the nightclub on the floor above.
06:36But she's sitting almost directly below the column on the dance floor that cracked the night before.
06:5110-10 a.m.
06:53A customer comes into the bank.
06:56She's out of breath, saying there's a problem in the basement car park.
07:00Debris is falling down.
07:01The customer told us that the bank is going to collapse.
07:06Xiong stays in the bank, whilst Christina and a colleague rush down to the basement to investigate.
07:19Although none of the cars are damaged, as they're leaving they see two men in overalls working by a cracked
07:24column.
07:27There's debris on the floor, but the workmen say everything is fine.
07:33Reassured that it's nothing serious, they go back to work in the ground floor bank.
07:45Two floors above, in the hotel reception, staff see cracks and fissures spreading across the wall.
07:54But down below, Xiong and Christina are unaware of any further problems.
08:06Throughout the building, vital supporting walls and pillars are starting to fracture.
08:11The hotel New World is on the brink of collapse.
08:18Something extraordinary is happening within an unremarkable building in Singapore's Little India.
08:26Cracks are spreading throughout the walls and supporting columns.
08:32But in the bank on the ground floor, assistant manager Cheong is oblivious.
08:36He's wondering how his wife Cece has done in her exam.
08:39I wanted to see how she fare during the exam.
08:44It's 11.22am.
08:47Further back, Christina is finishing off the week's work when she's startled by a sound.
08:54It's falling debris.
08:56I actually did not know what's happening.
09:00And now she starts to feel vibrations all around her.
09:04We can feel the floor shaking.
09:0911.26am.
09:10Now the whole building is starting to shake uncontrollably.
09:18Pillars are cracking.
09:20Walls are giving way.
09:27An unstoppable, catastrophic collapse is set in motion.
09:33It was very sudden.
09:35One instant you are working.
09:37The next instant it's all pitch dark.
09:40Thousands of tons of steel reinforced concrete rain down on the people inside.
09:50In one terrifying minute, the Hotel New World suffers total structural failure.
10:02Trapping dozens of people.
10:12What was once a local landmark and a place of work, is now just a huge mound of rubble, surrounded
10:18by an enormous cloud of dust, visible for kilometers around.
10:28All six stories of the building have been destroyed, transformed into a concrete tomb.
10:35Christina, John, and other bank staff are buried at the very bottom of the building rubble, in the pitch black
10:41basement car park.
10:44We couldn't see anything, we couldn't hear anything.
10:47We couldn't even see the, our hand.
10:50John can't see his colleague Christina, even though she's just a meter or two away, pinned down by massive concrete
10:57slabs.
10:58I was just like laying in the coffin.
11:00I couldn't move at all.
11:06Back on the surface, it's a scene of total devastation.
11:13News crews film local people frantically clambering onto the wreckage.
11:19They furiously manhandle rubble, desperately searching for any survivors.
11:3311.35 a.m.
11:35Within eight minutes, emergency workers start arriving.
11:44Singapore's top military medic, Dr. Lim Menkin, rushes to help.
11:49He's stunned by the scale of this unprecedented catastrophe.
11:54This is the biggest disaster since World War II.
11:58The terrible news is spreading to grief-stricken relatives who mingle amongst the crowds of stunned onlookers.
12:06It's a scene of total bewilderment and rising dread.
12:13Around noon, over half an hour into the disaster,
12:16Cheong's wife, Cece, arrives and realises that her husband is buried somewhere inside the mountain of rubble.
12:23She has no way of knowing whether he's dead or alive.
12:28She finds her uncle, who happens to be a structural engineer, but he can offer her no real comfort.
12:34I remember asking him, what are the chances of Cheong surviving in such a collapse?
12:41He told me, we should just hope for the best.
12:45About 10 metres from Cece, below the rubble, the husband Cheong is fighting off the panic.
12:51But all around, other survivors, like his colleague Christina, are aware of mounting hysteria.
12:57I can hear a lot of people crying.
12:59He was asking for help.
13:01Some of them were screaming, and some of them were crying in pain.
13:07Some of the survivors are badly injured,
13:10but assistant manager Cheong is determined to keep everyone calm.
13:18I thought it's a matter of time people will come to rescue us.
13:3012.30pm.
13:32About one hour after the collapse, back on the surface, there's good news.
13:36The rescue teams find a survivor, a tourist, who is staying on the top floors of the hotel.
13:45Shortly afterwards, they haul a second survivor, a local shopkeeper, from the hotel debris.
13:55Huge cranes are now brought in from across the island.
13:58They start working from the top floors of the hotel, down through the devastated building.
14:05Close to 5.30pm, six hours into the disaster, the rescue workers hear the faint voice of a young woman.
14:29the young woman's name is oiling she was working in the hotel reception on the third floor she's
14:35just 19 years old her right leg is trapped under a huge concrete slab dr. Lim is horrified knowing
14:43that if they simply pull her from the rubble she may go into shock the act of freeing her leg
14:50and
14:50allowing her blood to start flowing again could release deadly toxins from the wound into the
14:55rest of her body killing her the condition is called crush syndrome it's impossible for dr.
15:04Lim to know for sure whether oilings leg is crushed so he takes the only decision he can
15:09to amputate the leg right on the spot it's a tough call as the medical team sterilize their instruments
15:19the rescue workers continue working feverishly to free the young woman they know their desperate
15:27efforts may end in tragedy but suddenly they find they can move this lab a few centimeters
15:37they haul oiling from the rubble dr. Lim swoops on her and examines the leg worried that toxins will
15:44now be flooding into her body but his fears are unfounded the the wonder of it was when we looked
15:52at the leg
15:53he was undamaged you know oilings foot was trapped under the concrete slab by a pile of telephone directories
16:05it's a minor triumph on a day of deep sorrow
16:13the rescuers hastily put together a list of all those known to have been in the building when it collapsed
16:19they can account for everyone known to have been in the hotel on the top four floors
16:2517 are dead and 11 have been rescued alive
16:31the nightclub on the floor below was empty but the ground floor bank is a different matter
16:39their list reveals that up to 20 people including chong and christina were working there when the
16:44building collapsed and will be buried at the very bottom of the rubble
16:48in the building
16:5411.30 p.m.
16:5812 hours after the disaster the rescue teams are working through the night trying to reach the bank
17:07heavy machinery hauls huge slabs of debris away from the top
17:15but the rubble is very unstable and shifts dangerously
17:24some ten meters below the glare of the rescuers arc lights with vibrations shaking the wreckage the horror is growing
17:33the survivors are trapped in a dark tomb under six thousand tons of concrete and steel
17:43assistant manager chong is just within reach of one of his bank colleagues who's lying injured nearby crushed by a
17:50beam
17:50he tries desperately to push the beam away but it's too heavy
17:55i felt very helpless your colleagues here dying and then you can't do anything at all
18:02that was uh that was bad
18:08chiong realises his efforts are in vain
18:12good smell stench of death
18:16it's it's very sad
18:18your own colleague you've been working for so many years with
18:21and all of a sudden he's gone
18:24the crushed masonry is preventing the circulation of air oxygen is beginning to run out
18:34just a meter or two from chong christina is becoming desperate
18:37i was thinking i'm still very young i still got lots of things to do and i'm not married yet
18:45i i can't just die like that
18:53back on the surface the rescuers still have ten meters of rubble to dig through
18:59at this rate it'll take days to reach chong and christina
19:04with the oxygen getting thinner this is time they just don't have
19:14midnight
19:16half a day has passed since the collapse of singapore's hotel new world building
19:23only eleven people have been pulled alive from the rubble
19:28christina and chong are trapped deep in the basement car park
19:39a team of irish engineers working on the nearby subway construction is watching the rescue work
19:45subway tunneller tommy gallagher is especially concerned that the use of heavy machinery may be causing the rubble to shift
19:52and fall
19:52potentially endangering the lives of any survivors buried at the very bottom of the mound
19:58we kept saying to the senior people in charge we think there is people in that building alive
20:04and what you're doing here you're going to kill them
20:08they propose a radical alternative abandoning the use of cranes to clear the rubble from the top
20:13and instead tunneling deep into the foundations of the building to get survivors out
20:21it's a very difficult decision but around dawn the authorities give the green light to tommy and his colleagues
20:30the irish engineers have no idea exactly where in the basement any survivors may be
20:37after close examination of the building plans they decide the quickest way to get into the car park
20:42is to break through ventilation shafts accessible from street level
20:48a rescue camera reveals a scene of devastation
20:52the tunnelers have to wade through knee deep water and push past crushed cars
20:58to their horror they can smell petrol
21:03they know a single spark could set up a devastating explosion
21:08the car park is a death trap
21:11that's what we were worried about
21:12any spark of a machine or england
21:18the subway engineers have an agonizing wait
21:20whilst the water and petrol are pumped out
21:27then they start hacking a makeshift tunnel through the debris
21:30using small hydraulic jacks to support the thousands of tons of rubble above
21:39Sunday 7 p.m.
21:42it takes seven hours to tunnel nine meters
21:47the ground so unstable above us everything we were just taking a chance like
21:51then their worst fears are realized
21:56it started to close on us
22:05the tunnel caves in
22:07Tommy and his mates scramble out moments before the roof collapses
22:11their path is totally blocked
22:18Sunday 7.30 p.m.
22:25Xiong and Christina have been buried in the stifling claustrophobic darkness for 32 hours
22:30they have no idea rescuers are trying to reach them
22:34undeterred by the cave-in
22:36the Irish engineers start digging more tunnels in the dangerous building rubble
22:41willingly risking their lives
22:43the tunnelers were the bravest people I've ever met in my life
22:47and the way they went about it
22:49the spirit
22:50it's a spirit that's very rare
22:52really
22:55tunnels two and three are built from the southeast
22:57but the subway engineers soon find their path blocked by huge slabs of debris
23:02with tunnel one still too dangerous after the cave-in
23:06a fourth tunnel is dug northwards
23:08it takes all night
23:09but Tommy and his mates crawl under crushed cars
23:12and dig all the way around the exterior basement wall
23:15we worked around the clock we never went to bed
23:22Monday 7 a.m.
23:24Xiong and Christina have been trapped in the rubble
23:26for almost two days
23:27they're losing track of time
23:31we don't even know how many days he was trapped inside
23:33I was just trying to keep alive
23:37because I have a lot of things to live for
23:41then Xiong hears a noise
23:43we could hear rumbling sounds, you know, from the distance
23:50hoping that it's a rescue team
23:52the bankers start tapping frantically on the beams that are trapping them
24:19the tunnelers crawl ever closer to Xiong and Christina
24:22they feel they're on the verge of reaching them
24:25but they face one last obstacle
24:29and all of a sudden we had a meter square concrete beam
24:32and it was right in front of us
24:33we're headed smack on
24:34so they were on the other side of that
24:38they have no idea where in the building the beam came from
24:42but they're desperately concerned that it's helping to support the weight
24:45of the collapsed building above them
24:506,000 tons of rubble
24:52are balanced delicately above the heads of Christina, Xiong
24:55and now the tunnelers
25:00it's noon on Monday
25:02two days into the disaster
25:05the rescue workers decide they have no choice
25:08except to break through the huge concrete beam
25:11Dr Lim joins them, ready for any emergency
25:14you don't think of the danger
25:16there's somebody at the end of the tunnel
25:18and you want to reach that person
25:20the tunneller's drills carve through the concrete surprisingly fast
25:26a few meters away, in the darkness
25:28Xiong hears the drilling getting louder
25:35they keep asking me, can you see a light?
25:37can you see a light?
25:38you know
25:42finally I could see
25:43there's a chink of light from somewhere
25:47soon, Xiong is able to see the rescuers
25:50just the other side of the hole
25:53the tunnelers are terrified
25:54that they may have cut through a major supporting beam
25:57they fear the rubble could come crashing down at any moment
26:01they tell Xiong to stay where he is
26:04whilst they prop up the route
26:05I said no thank you, I'm coming out
26:08Xiong cannot bear to stay another moment in the darkness
26:10he scrambles towards safety
26:14he just ran
26:16I said don't blame me either
26:18because he thought he would never come out of there alive
26:20he said
26:26after two days buried alive
26:28Xiong is able to walk out into the daylight
26:30with just a few scratches
26:32that was really a miracle
26:36Christina is buried deeper in the rubble
26:39it takes another seven hours to rescue them
26:48Dr. Lin leads Christina away on a stretcher
26:53later examinations reveal her only injury
26:55is a black eye
27:01I feel just like a hero
27:03or something like that
27:07Chiong and his wife Sisi
27:09are finally reunited at the hospital
27:12it was such a moment of joy
27:14such great joy
27:17you just feel that life is very fragile
27:20anytime it can be taken away from you
27:22you just, just live, live
27:25thanks to the pioneering use of tunnels
27:27to dig into the very deepest parts of the rubble
27:30six more survivors
27:31are ultimately pulled alive
27:33from the wreck of Hotel New World
27:36in all
27:3717 people have been saved
27:42but 33 have lost their lives
27:49now by rewinding the events of that fateful day
27:53and by going deep into the investigation
27:55we can reveal what really happened
27:57to the Hotel New World
27:59advanced computer simulation will take us
28:02where no camera can go
28:03into the heart of the disaster zone
28:07a commission of inquiry will be appointed
28:09to seek answers to the many questions
28:12raised in this, the worst building disaster in Singapore
28:17the investigation team includes Terry Hume
28:20a structural engineer based in Singapore
28:23he has decades of experience in major building construction
28:27Hume visits the site within hours of the collapse
28:29and is shocked by what he sees
28:32the first impression was that the whole collapse
28:35must have been very rapid
28:38and the whole building must have collapsed at the same time
28:41it was clearly something unusual
28:45in a city like Singapore
28:47it's everyone's worst nightmare
28:49similar buildings are everywhere
28:51and much taller structures
28:53soar skywards all across the island
28:56the investigators need to find out
28:59why the Hotel New World collapsed
29:01and fast
29:07how did a six story reinforced concrete building collapse
29:11in fewer than 60 seconds
29:14until the investigators find out
29:16the lives of millions who live and work in similar structures
29:19throughout Singapore
29:20could be at risk
29:23the team interviews locals
29:25who remember that 10 years earlier
29:26a gas leak knocked out 35 people at the hotel site
29:32could gas have escaped again causing an explosion
29:36or worse, could there have been a bomb?
29:47it's investigator Terry Hume's first hunch
29:50he knows that explosions leave telltale signs
29:53what the experts call a distinctive signature
29:56the immediate effect of the explosion is normally to certainly blow out the windows
30:01possibly blow out the sidewalk
30:06you would see some sort of evidence of this explosion blowing the debris out or window shattered
30:18but the unique marks of an explosion
30:22shattered glass and crushed rubble
30:23blown hundreds of meters from the disaster site
30:26simply do not exist
30:29there was nothing like that
30:31eyewitnesses state that the building collapsed straight down
30:34folding like a pack of cards
30:36the whole thing dropped like that
30:38just goes in
30:40but if a bomb was responsible for the destruction
30:42there should be other signs
30:44such as traces of explosive substances
30:48forensic police officers meticulously scour the site
30:51for any chemical residues
30:54they find nothing
30:57so, if it wasn't an explosion
30:59what could have caused the collapse?
31:02it really is quite difficult to demolish a complete building very neatly
31:05the team needs to investigate the disturbing possibility
31:08that the building materials were defective
31:11this is the wall here
31:13they interview the Irish tunnellers
31:14and learn that some of the concrete was so soft
31:16their drills went through it like butter
31:21could it be that the concrete was badly mixed in the first place
31:25undermining the strength of the building
31:27with millions of lives depending on similar materials throughout the city
31:31it's an horrific thought
31:34the team takes 240 concrete core samples
31:37to one of Singapore's top laboratories
31:41of these 80 are quickly dismissed as being unusable
31:44unsuitable for testing
31:47the scientists examine the remaining 160 cores
31:51to see whether the correct ratio of sand, stones and cement was used
31:56then, they perform concrete strength tests on them
32:05the cores do fracture
32:07but only under very heavy loads
32:10the materials they test meet internationally accepted safety standards
32:14it was a disappointment
32:16because that was the easy solution
32:18if the concrete had been poor quality
32:20you'd have immediately had an answer to why it collapsed
32:23Hume concludes the reason the concrete seemed soft
32:26was because it was fractured during the violence of the collapse itself
32:33so, if it isn't defective building materials
32:36what else could have caused the disaster?
32:39the investigators turn to another terrifying scenario
32:42one that like the concrete could have implications for the entire city
32:48they look at the land on which the hotel was built
32:51and discover like much of Singapore
32:53it used to be a swampy flood plain
32:56drained from the 19th century onwards
32:58this was fine for the construction of small buildings
33:01but like much of the booming city
33:03the Hotel New World was significantly taller
33:05bigger than anything built a hundred years ago
33:08if the reclaimed ground was unstable
33:11could the collapse be just the beginning of an island-wide disaster?
33:20the first step is for the investigators to examine the surviving basement walls
33:27if the foundations had moved in the unstable ground
33:30if the foundations had moved in the unstable ground
33:31these should show evidence of catastrophic cracks
33:38intriguingly, they find nothing
33:41to make sure, they analyze the composition of the soil
33:47the team drilled deep into the ground to take samples
33:54leaving nothing to chance
33:56leaving nothing to chance
33:56they also test the strength of parts of the foundations that survived
34:04finally, after weeks of work, the results come through
34:14although there was evidence of some small ground movements
34:17the team is forced to conclude
34:19that it was not enough to have brought down the building
34:22it became clear that there hadn't been a failure in the foundations
34:26they were quite reasonably well constructed
34:29with yet another avenue closed
34:31the team turned their gaze even further underground
34:36could the construction of Singapore's new subway
34:38have weakened the building's foundations and caused it to collapse?
34:44when you build an underground railway in any town
34:47anything that goes wrong
34:49is immediately laid to the blame for the underground railway
34:54could the subway tunnelers be responsible for the disaster itself?
34:59it was a bit of a kick in the taste to it really, yeah
35:03the investigators quickly establish
35:05that the closer of two nearby subway tunnels
35:07is less than a kilometer away
35:10what effect could this have had on the building?
35:18subway tunnels have collapsed before
35:22just a year earlier in South Korea
35:24this building fell into one
35:31it only happened because the building was almost directly above the tunnel
35:36but could there be an unknown mechanism by which the subway was responsible?
35:41the Singapore investigators measure the diameter of the tunnel
35:45and calculate the ground movements that vibrations would have caused
35:48even taking this into account
35:51it seems an unlikely solution
35:55Professor Jonathan Wood is a world expert
35:57who studied the dynamics of building collapses for over 20 years
36:00if you are within two diameters of the tunnel
36:05you can expect quite an effect
36:07here they were hundreds of yards away
36:12the team concludes that the subway tunnels were simply not close enough
36:16to have been responsible for the collapse
36:20Tommy and the tunnelers are in the clear
36:23we knew it was something that happened in a freak accident
36:26and that's exactly what it was
36:32it's now clear that the collapse of the Hotel New World
36:34has not been caused by an explosion
36:39by shoddy construction
36:42by swampland
36:43or by subway tunneling
36:48the buildings don't just collapse
36:51it's like a murder investigation
36:53you must find who is responsible
36:57the investigators know they must be missing a vital piece of evidence
37:03it soon arrives from a very unlikely source
37:10the nightclub
37:13the nightclub
37:14the police interview the women who were working in the first floor club
37:17the night before the collapse
37:22the nightclub hostess tells them how
37:24as she was setting up the bar
37:27a pillar on the dance floor cracked
37:34the investigators consult the building plans
37:37which show this is column 26 out of a total of 36
37:43they know that a failure of one supporting pillar
37:45should not have brought the entire building crashing down
37:55the hostess tells them that shortly afterwards workmen started fixing wooden beams to the pillar
38:03the building owner came to inspect the damage
38:09then they interview one of the girls who was working in the nightclub
38:15she tells them how she was checking her makeup in the dressing room
38:19when the mirror shattered
38:24the mirror was attached to another support pillar
38:27column 32
38:30the investigators now know that a second pillar was close to failure
38:36when the pieces start falling off columns
38:38you are very very near
38:40the point of which the column will collapse
38:47next the team interview survivor Christina Foer
38:51she tells them how on the morning of the disaster
38:53she went down to the basement car park
38:55and saw workmen propping wood against the column
38:59the pillar had cracked and there was plaster on the floor
39:04they identify this as column 30 and it was also failing
39:10it's a crucial breakthrough
39:12there are now eyewitness accounts that three columns were failing in the hours leading up to the disaster
39:18for the first time the investigators know that three vital supporting columns were stressed right to the limit
39:31there had to be something very badly wrong with the building but what could it be
39:38as a last resort the team starts looking at cutting edge laboratory research into a little known phenomenon that could
39:45provide the answer
39:47when concrete is stressed to near breaking point
39:50tiny cracks can start spreading deep within the heart of the material
39:56not only are these micro cracks as they're called potentially deadly
40:01but frighteningly they're invisible to the naked eye
40:05you can only see them under a microscope
40:08it's impossible to know for sure whether the crucial supporting columns of the Hotel New World were suffering from this
40:14dangerous disease
40:17but if micro cracks are ignored
40:19they eventually cause the surface of pillars to fracture
40:24greatly reducing the amount of weight they can support
40:27at this point the building would be on the verge of collapse
40:32if the team is correct
40:33like woodworm eating away timber from within
40:36micro cracking would have weakened the concrete columns in the building
40:40until they were effectively rotten
40:47but where could the extra weight that causes micro cracking have come from
40:56as the site is being cleared
40:58the investigators see massively heavy objects being pulled from the rubble
41:04they examine the blueprints to see whether these were allowed for in the original plans
41:10and make a startling discovery
41:12during the 15 years of its lifespan
41:15the building owner added extra loads to the Hotel New World
41:18that were not part of the original design
41:21the team learns that in 1975
41:23the bank built a steel reinforced strong room
41:27weighing 22 tons on the ground floor
41:37then in 1978
41:38the building owner installed two air conditioning towers
41:42adding extra weight
41:48in 1982
41:49to improve the buildings lacklustre appearance
41:53workmen fixed heavy duty ceramic glazed tiles to the exterior walls
41:57the weight
41:58over 50 tons
42:05finally in 1986
42:06before the collapse
42:07the building owner installed yet another air conditioning tower on the roof
42:12to make conditions in the sweltering Singapore heat more comfortable
42:23the investigators believe all this extra weight must have been too much to bear
42:30all modern buildings are designed to support what the experts call the dead load and the live load
42:37the dead load is the weight of the building itself
42:40but for the investigators the crucial calculation is the live load
42:45the extra weight consisting of people and objects ranging from air conditioning towers to furniture
42:50which a building has to support
42:56could the building support over 100 tons of extra live load placed upon it
43:01the answer is a big surprise
43:04the calculation showed that the live load was adequately supported
43:10set against the 6,000 ton weight of the building itself
43:13the live load including over 100 tons of strong room tiles and air conditioning units
43:19was insignificant
43:20it should not have caused the buildings 36 pillars to give way
43:27the team is back at square one
43:33after months of painstaking work
43:36they still don't know what happened
43:44the team is certain they must have missed some vital clue
43:47that it will enable them to understand why Singapore's Hotel New World collapsed
43:52they return to the blueprints
43:54and pour over photos of the damaged columns again and again
44:00clutching at straws
44:02they double check the calculations made by the draftsmen
44:04for the weight of the building itself
44:06the dead load
44:11what they find is a revelation
44:13a fatal mistake
44:15that means for the entire 15 years after its construction
44:18the building was on the verge of catastrophe
44:24the amazing thing was basically this draftsmen allowed for the live load
44:29and he forgot the dead load
44:31it's an astonishing discovery
44:33a schoolboy mistake
44:36the calculations made by the draftsmen were so badly wrong
44:40that key columns
44:42such as 26 and 32
44:44could not even support the weight of the building itself
44:49even without all the extra live load
44:52the air conditioning units
44:54heavy duty glazed tiles and bank strong room
44:57for 15 years
44:58many of the pillars that were supporting the building
45:01had been right at the limit of their strength
45:04the collapse
45:05was just a matter of time
45:10all the columns were very near failure
45:13had been sitting close to the edge for 50 minutes
45:17the investigators finally understand why the disaster happened
45:23now by rewinding the events leading up to that fateful day
45:26and by following the process of the extensive investigation
45:29we can finally reveal what really happened to the hotel New World
45:39Friday, March 14th, 1986
45:44for 15 years, hidden from human eyes
45:47deadly micro-cracks were spreading deep within the concrete columns of the Hotel New World
45:567pm
45:5716 hours before the collapse
46:02column 26 cracks in the nightclub
46:06it's weakening and starts to pass its load to surrounding pillars
46:12about 13 hours before disaster
46:15column 32 can't support the extra load and starts to fracture
46:19this causes a mirror attached to it to smash
46:25just over one hour from disaster
46:28load from the two nightclub columns is being transferred to column 30
46:32it starts cracking
46:34this time in the basement car park
46:45four minutes before disaster
46:47four minutes before disaster
46:48above Christina, column 26 starts to collapse
46:52causing debris to billow down and vibrations to spread throughout the bank
46:59as three columns collapse the building reaches the point of no return
47:04an unstoppable chain reaction is set in motion
47:08if you've got your pack of cards
47:10all you've got to do is knock one card out
47:13and all the other cards follow suit
47:21the entire building crashes to the ground in under 60 seconds
47:27killing 33 people
47:39Tragically the investigators now know there were plenty of warnings that the hotel was about to collapse
47:47if the building owner had told the authorities that three columns were cracking
47:51instead of ordering workmen to patch them up
47:53disaster could easily have been averted
47:59I believe any structural engineer would have immediately said that you needed to evacuate the building
48:0533 lives could have been saved
48:1633 lives could have been saved
48:18Survivors Jong and Christina will always remember their colleagues who died in the Hotel New World collapse
48:24I do miss all my colleagues
48:26They are the best I ever have
48:30But they will also never forget the courage of the subway tunnelers
48:37It was volunteering and they had to dig through debris which might just fall on them at any time
48:45Without them I would not be here
48:47So I would like to thank them very much on this
48:54Tommy Gallagher and the subway tunnelers were awarded one of Singapore's highest peacetime honours
48:59The Conspicuous Gallantry Medal
49:06Lessons have been learnt from the tragedy
49:08Singapore completely overhauled its building regulations
49:12To ensure that all dead and live load calculations made by architects
49:16Would in future be independently checked
49:19A crucial extra safeguard that has been adopted by many other countries
49:25Like many cities Singapore continues to build ever upwards
49:31Mercifully building collapses are a rare event both in Singapore and throughout the world
49:39But when they happen the courage and dignity of ordinary people shine through
49:53To be continued...
49:56To be continued...
50:02To be continued...
Comentarios