Tag Disasters

Master of Disasters

Highlights from my time on the What Went Wrong beat for Popular Mechanics…

5 Terrible U.S. Road and Highway Designs: Lessons Learned

8 of the Most Dangerous Places (To Live) on the Planet

What Went Wrong: How the Dallas Cowboys’ Field House Collapsed

What Went Wrong: Investigating Russia’s Biggest Dam Explosion

6 Safe, Strong—and Chic—Bomb Shelters You Can Buy Now

5 Terrible U.S. Road and Highway Designs: Lessons Learned

By Joe P Hasler | Popularmechanics.com | August 24, 2010

Whiling away the hours in roadwork-induced stoppages, you might find yourself cursing the traffic engineers and highway designers responsible for your misery. You might praise them for finally doing something about that particularly sticky wicket of an interchange. And you might wonder to yourself, “If there was a perfect highway, what would it be like?” At least that’s what we wondered. So we found some of America’s worst examples of highway design, and talked to experts in the field to find out what it takes to build good roads.

LESSON NO. 1 ||| DON’T BULLDOZE HOUSES FOR ROADS


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The Offenders: The Cross-Bronx Expressway, New York City; The Alaskan Way Viaduct, Seattle


To the 21st-century American, the idea of razing homes to make room for more roads may seem inconceivable, or at least dated. Our metropolises might be strangled with congestion, but you’d be hard-pressed to find a traffic engineer or highway designer who thinks more urban expressways are the solution. That wasn’t always the case.

In the immediate post-war years, massive highway projects reshaped vast sections of the urban landscape. In New York, whole neighborhoods disappeared, and more than 5000 families were forced to move when master builder Robert Moses ran the 8.3-mile Cross-Bronx Expressway, a vital link in his vision for a massive network of urban expressways, through a densely populated segment of the Bronx. In the years after 95 divided the Bronx, the neighborhoods to the south, cut off from normal street traffic flow and related commerce, quickly faded into the blighted, burned-out south Bronx of the 1960s.

Across America, similar projects floundered in the face of community protest. The so-called “highway revolts” of the 1960s and 1970s brought central urban expressway expansion to a halt. According to Steve Alpert, a highway engineer trainee with HNTB, who studied the lessons of the Cross-Bronx Expressway at MIT, “You still never see inner-city freeways being built anymore.”

What you do see, though, is cities grappling with the legacy of old urban expressways. Seattle, for example, is currently considering a proposal to replace its Alaskan Way Viaduct. Built in the 1950s, the elevated, double-decked highway runs 2.2 miles along central Seattle’s waterfront. “This has been the center of a great debate; why put a viaduct on the waterfront?” says Ron Paananen, who is the project administrator for the proposed replacement of the Viaduct.

“It’s a barrier to Seattle reaching its world-class waterfront,” Paananen says. Recognizing this, Washington’s Department of Transportation wants to tear down the Alaskan Way Viaduct and replace it with a tunnel. “That would eliminate the grid obstruction and actually reconnect cross streets,” Paananen says.

 

LESSON NO. 2 ||| IF YOU BUILD IT, THEY WILL COME: SO PLAN FOR THAT


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The Offenders: Interstate 25, The Valley Highway, Denver


Originally built between 1944 and 1948, the Valley Highway in Denver is one of the older segments of the Interstate Highway system. Freeways, though, tend not to age gracefully, and this particular stretch is no exception. When it was built Denver’s population hovered around 600,000. Since then, it’s quadrupled to 2.4 million. Now, 200,000 vehicles use the Valley Highway each day, and according to Steve Hersey, a traffic engineer with the Colorado Department of Transportation, certain sections of the road are “almost always backed up.” One major contributor to the congestion is the spacing, or lack thereof, between I-25’s interchanges.

“When you look at these older roads, typically what happens is you start out and you have decent spacing,” Hersey says. “But as roadside areas develop, which they tend do when you build a freeway past them, and you start adding interchanges, that’s when you get into trouble.”

While many of the interchanges on the Valley Highway are ¾ or just ½ mile apart, standards of highway design typically call for a mile between interchanges. Anything less than one mile makes it difficult to effectively place signage and adequately warn drivers of upcoming exits. Drivers also have less time to react. All of this contributes to increased amounts of weaving and merging.

 

LESSON NO. 3 ||| CONSIDER THE EARTH YOU BUILD ON: GEOLOGY MATTERS


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The Offenders: Interstate 10, Louisiana; The Alaskan Way Viaduct, Seattle


Every year, Overdrive magazine, a trade publication for long-haul truckers, polls its readers to determine the state with the worst roads in the country. For a number of reasons, Louisiana is a fixture at the top of the list. As one driver told the magazine in 2008, Interstate 10, which runs east-west across the entire state, is “rougher than a corncob.” The truckers aren’t the only ones who have noticed.

“You know you’re here from the bumps,” says Richard Levinson, a travelling jazz musician who works out of New Orleans in the winter. “As soon as you hit Louisiana, even if it’s dark and you can’t see the signs, you can tell.”

One explanation for the rough and rumbling roads of Louisiana is the soft turf on which they are built. Speaking to Overdrive in 2008, Mark Lambert, then communications director for the Louisiana DOT, said “Over time, you get waves in the concrete as the loose soil shifts or sinks, and if you’re in a long wheelbase vehicle, that gets pretty bumpy. You’ll get a bump about every 50 feet.”

In Seattle, the issue isn’t soggy soil, but shifting plates. One major factor driving the efforts to replace the Alaskan Way Viaduct is that the stacked highway is no way engineered to withstand the magnitude of earthquake Seattle, smack-dab in the middle of the Cascadia Subduction Zone, is susceptible to experiencing. In fact, the current viaduct is built in the same style as the Cyprus Viaduct in San Francisco, which famously failed in the 1989 Lomo Prieta earthquake.

“Over the past few decades I think there’s been a dramatic increase in understanding these issues, and advancement in the building codes to address them.”

 

LESSON NO. 4 ||| EVEN THE LONELIEST HIGHWAYS NEED A LITTLE LOVE (AND AMENITIES)


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The Offenders: Utah Route 95, The Bicentennial Highway


Of course, linking major cities isn’t the only role of the American highway. They also provide access to the remotest spots in the country. And it doesn’t get much more remote than Utah State Route 95, otherwise known as the Bicentennial Highway. Stretching 165 miles across the high red desert between Hanksville and Blanding, the Bicentennial Highway offers a unique lesson—even roads in the middle of nowhere require attention and amenities.

End to end, Route 95 can take four hours to drive, and there’s very little in between. Along the way there are no rest areas or commercial facilities. There’s no place to buy gas, get food or stop for repairs. The pit toilets at Natural Bridges National Monument represent one of the few signs of civilization.

Kevin Kitchen, a liaison with the Utah Department of Transportation who specializes in the state’s southeastern transportation issues, says the major concern with the Bicentennial Highway is how its relatively low rate traffic volume affects road conditions. As a main access road for Lake Powell and several national recreation areas, including Natural Bridges, traffic is mostly seasonal. Those who do drive it, Kitchen says, know what they’ve bargained for. “Many motorists traveling through this area of the state comment that they choose this route precisely because of the isolation and the ability to escape roadside amenities,” he says.

But while drivers may be able to abide pit toilets and no service stations, unusable roads are another matter, and one that Utah DOT treats with extreme vigilance.

“Most of our current design efforts focus on preserving the pavement due to the typically low traffic volume,” he says. “The remote location and high desert altitude can pose maintenance and construction challenges, primarily because of the cost of mobilization.”

 

LESSON NO. 5 ||| NEVER UNDERESTIMATE THE VALUE OF A SHOULDER


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The Offenders: The Pulaski Skyway, Newark to Jersey City, New Jersey; The Valley Highway; The Cross-Bronx Expressway


Built between 1930 and 1932, and linking Manhattan, by way of the newly constructed Holland Tunnel, to the transcontinental Lincoln Highway, the 3-mile-long Pulaski Skyway was effectively the final section of America’s first superhighway. Unfortunately, it stands today as one of the earliest lessons of how not to build a highway.

For one thing, its design was inspired by steel truss deck rail bridges of the era, and was based on the railway design principles of Arthur Mellon Wellington, whose book, The Economic Theory of the Location of Railways, was first published in 1887. A central railway principle was keeping land-acquisition costs down by employing the narrowest possible right-of-way. Applied to the Pulaski Skyway, the result is inadequately narrow roadways. Its two 24-foot-wide road decks allow for just two 12-foot lanes of traffic—the minimum width allowed for highway lanes—leaving no space for a shoulder, and very little margin of error for the modern driver.

“The value of the shoulder was not fully understood in the early days of highway design,” says Steve Hersey, a Colorado DOT traffic designer. Now, road planners ideally look to have at least ten feet of shoulder on the side of a highway. One element of this is to give drivers a breakdown lane. But Hersey says that as the width of a shoulder shrinks it also affects how people drive.

“The issue is capacity,” Hersey says. “If you have a shoulder that’s smaller than 6 feet wide, and you’ve got a guard rail or barrier wall, that will impact operation. Drivers become nervous. They overreact and slow down. They weave. And all of these behaviors affect the capacity of the road.”

http://www.popularmechanics.com/technology/infrastructure/a6420/5-terrible-us-road-and-highway-designs/

©2017 Hearst Communications, Inc.

 

8 of the Most Dangerous Places (To Live) on the Planet

By Joe P. Hasler | Popularmechanics.com | Sep 31, 2009 |

It’s hurricane season, a time of year when residents in vulnerable areas—like New Orleans—need to hunker down, stock up and prepare for the unforeseen. But there are other places in the world where the dangers are so great that it’s hard to believe anyone is willing to stay put and fight it out with Mother Nature. Here, we have canvassed the globe for 8 places that require fortitude, resourcefulness and a great faith in one’s DIY skills to make it through the year alive.


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1) The Cold Pole

Where: Verkhoyansk, Russia

On the frigid taiga, 3000 miles east of Moscow, deep in the heart of Siberia, sits Verkhoyansk, the oldest city above the Arctic Circle. For more than three centuries, Russians have continuously resided here, braving endless winters on the banks of the Yana River, which is frozen solid for nine months of the year. Today, approximately 1500 people live here.

Verkhoyansk lays claim to the title of coldest city in the world, the so-called Cold Pole. It’s hard to dispute the designation, when you consider that from September to March the city averages fewer than 5 hours of sunlight each day. (In December and January, there is nearly no sunlight.) Winter temperatures there typically fall between minus 60 and minus 40 degrees Fahrenheit. The low, recorded in the late 19th century, was minus 90.

Nowadays, the city is attempting to attract “extreme tourists,” who are drawn by the intense cold. For much of its history, however, Verkhoyansk was a preferred exile destination, used first by the czars, then later by the Soviets. In the 20th century, Verkoyansk’s population peaked at 2500 residents.


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2) The Mountain of Fire

Where: Mount Merapi, Indonesia

Even during its most tranquil periods, Mount Merapi, on the island of Java, smolders. Smoke ominously floats from its mouth, 10,000 feet in the sky. “Fire Mountain,” as its name translates to English, has erupted about 60 times in the past five centuries, most recently in 2006. Before that, a 1994 eruption sent forth a lethal cloud of scalding hot gas, which burned 60 people to death. In 1930, more than 1000 people died when Merapi spewed lava over 8 square miles around its base, the high death toll being the result of too many people living too close.

In spite of this volatile history, approximately 200,000 villagers reside within 4 miles of the volcano. But Merapi is just one example of Javans tempting fate in the proximity of active volcanoes—it’s estimated that 120 million of the island’s residents live at the foot of 22 active volcanoes.


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3) Haiti’s Perfect Storms

Where: Gonaïves, Haiti

First came tropical storm Fay on August 16. A week later, Hurricane Gustav blew through. Following in quick succession were Hurricanes Hanna and Ike. In the span of just one month, the coastal city of Gonaïves, one of Haiti’s five largest cities, found itself on the receiving end of four devastating tropical cyclones. When the last storm passed, Gonaïves had practically been washed out to sea. Much of the city was buried under mud, or submerged in filthy water that stood 12 feet deep in some places. The death toll ran close to 500.

But the storms of August to September 2008 weren’t the most deadly in Gonaïves’ recent history. In 2004, the city of 104,000 took a severe beating from Hurricane Jeanne. Three thousand Haitians died when the Category 3 storm hit and leveled large swaths of the city.

What makes Gonaïves so susceptible to destruction by hurricane? Aside from its coastal location on the Gulf of Gonve, smack-dab in the cyclone-inclined Caribbean, Gonaïves rests on a flood plain prone to washing out when inland rivers swell. Furthermore, Haitians rely on wood to make charcoal, their primary source of fuel, and this has led to massive deforestation of the hillsides surrounding the city. As a result, when the rains come, the hills around Gonaïves melt away and mudslides nearly bury the city.


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4) The African Lake of Death

Where: Lake Kivu, Democratic Republic of Congo/Rwanda

Lake Kivu, located along the border between the Democratic Republic of Congo and Rwanda, is one of Africa’s Great Lakes. Deep below the surface of this lake’s 2700 square miles, there are 2.3 trillion cubic feet of methane gas, along with 60 cubic miles of carbon dioxide trapped beneath the lake under the pressure of the water and earth. If released from the depths, these gases could spread a cloud of death over the 2 million Africans who make their home in the Lake Kivu basin.

The precedent for this concern stems from a pair of events that occurred in the 1980s at two other African lakes with similar chemical compositions. In 1984, 37 people died around Cameroon’s Lake Monoun in a limnic eruption. Three years later, at Lake Nyos, also in Cameroon, 80 cubic meters of CO2 were released from the water. Subsequently, 1700 people died from exposure to the toxic gas. These incidents were apparently caused by volcanic activity below the lakes, which triggered the release of the gas. Similar activity is believed to occur beneath Lake Kivu, causing many to worry that this area is next. A report from the United Nations’ Environmental Program went so far as to call the three bodies “Africa’s Killer Lakes,” and said Lake Kivu was cause for “serious concern.”


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5) The Ephemeral Isles

Where: The Maldives

The Maldives are such a dangerous place that Muhammed Nasheed, upon taking office in 2008, made it one his first items of business as the Maldives’ first democratically elected president to announce a plan to create a fund for financing the relocation of the entire population.

The Maldives is a confederation of 1190 islands and atolls in the Indian Ocean. Its highest point of elevation is little more than 6 feet, and, sometime in the not-too-distant future, it is likely to be swallowed whole by rising sea levels. A 2005 assessment by the United States Geological Survey, conducted after the 2004 Indian Ocean tsunami, called the Maldives one of the Earth’s youngest land masses, adding that they’re not long for life above water. According to the report, the islands “should be considered ephemeral features over geologic time.”

By President Nasheed’s reckoning, the people of the Maldives would be well-served to find someplace else—India or Sri Lanka were floated as potential refuges—lest they too become ephemeral. Recent events support his decision to invest money earned through tourism in a relocation fund: The 2004 tsunami, which occurred at low tide, swept over the island, leaving 10 percent of the country uninhabitable. Of the Maldives’ 300,000 citizens, one-third were left homeless, and more than 80 people died. In 1987, during so-called “king tides,” the capital of Malé, an island city covering 1 square mile, was completely inundated. The effects of these disasters were compounded by the mining of the coral reefs that surround the islands, which has made them highly susceptible to sea erosion.


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6 Hurricane Capital of the World

Where: Grand Cayman

The Cayman Islands, a British territory situated 150 miles south of Cuba, are best known as a tropical playground for the champagne and caviar set, who come to the islands for pristine Caribbean beaches, world-class diving, and lax banking regulations. Less alluring is the islands’ other reputation as “hurricane capital of the world.” According to the tropical-storm-tracking website hurricanecity.com, Grand Cayman, the largest of the three Cayman isles, is hit or brushed by at least one hurricane every 2.16 years, more than any other locale in the Atlantic basin. Since 1871, 64 storms have battered the low-lying limestone formation, often with catastrophic results.

In 2004, Hurricane Ivan, a Category 5 storm with wind speeds approaching 150 miles per hour, dumped a foot of rain on Grand Cayman. A 10-foot storm surge followed, submerging a quarter of the island. An estimated 70 percent of the island’s buildings were destroyed, and its 40,000 inhabitants were left without power or clean water for days.


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7)  The I-44 Tornado Corridor

Where: Oklahoma City/Tulsa, Oklahoma

More than 1 million people reside along the Interstate 44 corridor that runs between Oklahoma City and Tulsa, the Sooner State’s two most populous metropolitan areas. Each spring, as the cool, dry air from the Rocky Mountains glides across the lower plains, and the warm, wet air of the Gulf Coast comes north to meet it, the residents of this precarious stretch, locally called Tornado Alley, settle in for twister season.

Since 1890, more than 120 tornados have struck Oklahoma City and the surrounding area, which currently has a population of approximately 700,000. On May 3, 1999, an outbreak of 70 tornados stretched across Oklahoma, Kansas and Texas. Several of the most destructive storms swept through Oklahoma City, destroying 1700 homes and damaging another 6500. Even with modern prediction capabilities and early-warning systems, 40 people died when an F-5 twister tore through Oklahoma City. In addition to the loss of life, this display of natural devastation caused more than $1 billion in damage. Since 1950, the longest the area has gone without a tornado is five years—from 1992 to 1998. (As if making up for lost time, in the 11 months that followed that record lull, 11 tornados hit.) For only three other periods during the last half-century has Oklahoma City gone more than two years without a tornado.

Northeast of Oklahoma City, along the same track that most tornado-producing storms travel, sits Tulsa, which has experienced its own share of devastation at the hands of Tornado Alley’s storms. Between 1950 and 2006, 69 tornados spun across Tulsa County—population 590,000—though none proved as deadly as the 1999 storm that hit Oklahoma City. But because of its geography—the city lies along the banks of the Arkansas River and is built atop an extensive series of creeks and their flood plains—Tulsa is particularly vulnerable to the rain that accompanies Oklahoma’s severe weather. Major floods in 1974, 1976 and 1984 caused hundreds of thousands of dollars worth of damage.


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8 China’s Creeping Sandbox

Where: Minquin County, China

Trapped between two creeping deserts, the once fertile oasis of Minqin County, in northwest Gansu province, lives on borrowed time. The double whammy of a decade-long drought and the upriver diversion of water from its lifeline, the Shiyang River, have left Minqin to wither into the Tengger desert, which approaches from the southeast, and the Badain Jaran, closing in from the northwest. In total, since 1950, the deserts have swallowed up more than 100 square miles. During that same period, the population there has risen from 860,000 to more than 2 million.

As of 2004, the deserts were approaching at a rate of 10 meters per year. With more than 130 days of wind and dust each year, that rate is unlikely to slow. Faced with rapid desertification, the Chinese government has begun relocating displaced farmers, as arable land has decreased from 360 square miles to fewer than 60.

http://www.popularmechanics.com/science/environment/g244/4329314/

©2017 Hearst Communications, Inc.

 

What Went Wrong: How the Dallas Cowboys’ Field House Collapsed

By Joe P Hasler | Popular Mechanics | November 2010 |

When the Dallas Cowboys’ practice facility caved in, it was the perfect storm of bad weather and shoddy engineering.


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On the stormy afternoon of May 2, 2009, 27 newly minted Dallas Cowboys were finishing a workout in the team’s indoor practice facility when the hanging lights 86 feet above them began swaying. On the sidelines of the 83,000-square-foot field house—a tent-like steel-framed building with a tensioned fabric exterior—beat writers and photographers stopped watching the minicamp and stared at the fabric walls, which were snapping like a flag in brisk winds.

“I heard something long before I saw anything,” says photojournalist Arnold Payne. “It was this huge crash of metal and steel. You knew it was time to run. Just from the sound.”

It was the sound of a massive structural failure. Buckling under the winds, the facility’s western wall collapsed on top of the field. The roof and eastern wall soon followed suit. As people dashed for the exits, the fabric covering fell, enveloping them in darkness. Most of the 70 inside the building managed to escape safely. But 12 people were injured, some seriously.

The practice facility had been ­erected in 2003 at the behest of new head coach Bill Parcells. Summit Structures, an Allentown, Pa.–based company owned by Canadian firm Cover-All Building Systems, put up a $4 million, 406-foot-long field house over one of the fields at the Cowboys’ Valley Ranch campus. But in 2008, after the collapses of four similar Summit- or Cover-All-built facilities over a six-year period, the Cowboys requested structural reinforcements. Summit put in additional horizontal bracing, buttressed some critical structural points and re-covered the field house in a new exterior fabric, all to make the building more robust. None of it worked. So who—or what—was to blame for the collapse?

First to weigh in was the ­National Weather Service. Studying Doppler radar from May 2, it concluded that a phenomenon known as a microburst—a localized, concentric wall of air capable of traveling at speeds of up to 150 mph—was a major factor. But investigators at the ­National Institute of Standards and Technology (NIST) soon determined that weather wasn’t the sole culprit in the cave-in. “There was nothing unusual about this wind event in terms of its relationship to struc­tural design,” says Fahim Sadek, who co-authored the NIST report.

Investigators determined that the building, designed to withstand 90-mph winds, broke apart in gusts between just 55 and 65 mph. In its final report, published eight months after the collapse, NIST detailed a series of engineering failures—a progression of flawed calculations, incorrect assumptions and unexplained deviations from original plans. Wind load, the force applied to an object by blowing wind, was calculated for an average building height of 60 feet; the structure actually had a mean height of 67 feet. As a result, the load on the building was more than double what Summit had assumed. Engineers also assumed that the building was “fully enclosed,” but it had vents and several large openings for doors, affecting internal pressure—and wind resistance.

When the facility was upgraded in 2008, Summit calculated the new roof’s slope at 11 degrees; the actual slope was 21 degrees—so demands on the building were 68 percent ­greater. And Summit assumed the building’s fabric covering provided lateral bracing for the structure. NIST’s computer models showed that it did not.

The NIST report noted that tented structures like the field house are relatively unregulated, and the practice of counting the fabric as lateral bracing is a point of disagreement among engineers. Summit may not be around to weigh in on the debate: Cover-All, Summit’s parent, filed for bankruptcy in March. (Attempts to contact Summit were unsuccessful.)

In the wake of the collapse, other organizations with similar structures, including Texas A&M and the University of New Mexico, had engineers evaluate the safety of their facilities. But it’s not known how many buildings of this type exist—or how many could be suffering from structural deficiencies. But the takeaway from this disaster is clear: Engineering errors and inclement weather can be a tragic combination. The Cowboys’ structure was built to fail; it just needed a good push. And on May 2, it got one.

INSIDE THE TENT COLLAPSE


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THE BUILDING

The Cowboys’ practice facility was built by Summit Structures in 2003. Twenty-eight steel-truss gable frames, reinforced with steel webbing, created the 86-foot-tall facility’s structure. Sheets of fabric hanging from the frame formed the interior walls and ceiling, and a layer of tensioned fabric over the frame created the exterior walls and roof. In 2008, Summit upgraded the facility, purportedly to make it safer.

THE MICROBURST

At 2:57 pm on May 2, a localized pocket of cool air in the midst of a spring storm drops from the clouds to the ground. The cool air pushes outward, creating a “stagnation point” from which a concentric wall of wind—essentially an inverted tornado—travels at speeds between 58 and 62 mph, blowing northeast toward Valley Ranch, about 1 mile away.


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At 3:24 pm, the wind smashes into the field house (1). On the western wall of the structure, its critical joints—the so-called “knees”—strain under the wind load, which outweighs the load-bearing capacity of these vital members; they buckle (2). Failures at the knee and ridge (3) cause the north end of the facility to collapse onto the field. The fabric that created the walls and ceiling also falls, cloaking 70 people trying to escape in darkness.


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SOUTH END

As the north end collapses (1), the near-tornado winds blow the east side of the southern end of the structure over onto the neighboring outdoor practice field (2). Most of the players, staff and local media inside the building managed to escape ­safely, but 12 people were injured. Special teams coach Joe DeCamillis sustained a broken neck, and Rich Behm, a scouting assistant for the Cowboys, was paralyzed from the waist down.

http://www.popularmechanics.com/adventure/sports/a6449/how-the-dallas-cowboys-field-house-collapsed/

©2017 Hearst Communications, Inc.

What Went Wrong: Investigating Russia’s Biggest Dam Explosion

By Joe P. Hasler | Popular Mechanics | February 2010 |

August 2009: a major failure occurred at the Sayano-Shushenskaya hydroelectric dam in Russia. 75 people were killed, many were injured and 40 tons of oil were spilled in the Yenisei river. With nearly 100 gigawatts of installed electric dams in the United States, experts wonder, could it happen here? PM investigates.


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Rescue workers clear debris and search for victims near the wreckage of Sayano-Shushenskaya hydroelectric dam’s Turbine 2. The 1500-ton piece of equipment exploded out of its seating and flew 50 feet in the air on Aug. 17, 2009; 75 people died in the accident.

Just before 8 am on Aug. 17, 2009, workers on the morning shift stepped off a clattering Soviet-era tram and made their way past security and into position at the Sayano-Shushenskaya hydroelectric power plant in south-central Siberia. In the 950-foot-long turbine hall, custodians mopped the stone floors and supervisors handed out assignments. On the roof, a technician began installing a new ventilation system. Above him soared a concave dam 80 stories high and more than half a mile wide at the crest. When operating at full capacity, the plant’s 10 interior penstocks funneled water from the reservoir behind the concrete barrier to the hall below him, where it tore past the blades of 10 turbines, spinning them with tremendous force before being flushed out of the hydro plant and down the Yenisei River.

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Completed in 1978, the Soviet-era hydro station is Russia’s largest, with enough output to power a city of 3.8 million. It was undergoing extensive repairs and upgrades that morning, so more workers were in the hall than usual: 52 on the main floor and another 63 down in the bowels of the plant. Nine of the 10 turbines were operating at full capacity–including the troublesome Turbine 2, which had been offline but was pressed back into service the previous night when electricity production dropped because of a fire at the Bratsk power station, 500 miles to the northeast. A few minutes into his shift, the technician felt the roof begin to vibrate. The vibrations grew louder and gradually turned into a thunderous roar. Alarmed, he scrambled off the roof.

At 8:13 am, two massive explosions rocked the hall. Security guard Aleksandr Kataytsev told English-language news station RT that he was one level below the turbine hall when he heard “a loud thump, then another one, like an explosion, and then the room went pitch-black.”

Turbine 2–a 1500-ton piece of machinery topped by a power generator–blasted through the floor and shot 50 feet into the air before crashing back down. The penstock water that had been spinning the turbine geysered out of the now-vacant shaft at a rate of 67,600 gallons per second. Like a massive industrial waterjet, it tore down the metal joists over Turbines 1, 2 and 3; the roof there crumpled like aluminum foil and collapsed in a tangle of glass and metal.

Water continued to pour into the hall, flooding its lower levels and eventually submerging other turbines. The plant’s automatic safety system should have shut down the turbines and closed the intake gates on the penstocks at the top of the dam, but Turbines 7 and 9 still operated at full speed, in excess of 142 rpm, triggering the crackling short circuits that darkened the plant. Amateur video footage taken downstream at the time of the accident shows bright flashes and a huge explosion in the vicinity of Turbines 7 and 9 as a wall of water spews from the structural breach near Turbine 2.

As the water level rose, employees stampeded toward the main entrance. Fearing a total collapse of the dam, many phoned relatives downstream and urged them to seek shelter in the surrounding Sayan Mountains. Among the fleeing workers were several supervisors in charge of safety and emergencies, which added to the confusion. On the fourth floor, shell-shocked midlevel operators telephoned up the chain of command for a contingency plan. No one answered.

Using his mobile phone as a flashlight, security guard Kataytsev found his way to an exit and made for higher ground. At the crest of the dam, he and several other employees struggled to manually close the penstock intake gates. By 9:30 am they had sealed all the gates, and the destruction below ceased.

In the wake of the accident, rescue crews mobilized to search for survivors. RusHydro, the partially state-owned utility company that operates Sayano-Shushenskaya, assembled 400 employees to pump out the flooded turbine hall and pick through the twisted debris. Russian president Dmitry Medvedev dispatched Sergei Shoigu, his emergencies minister, and Sergei Shmatko, the energy minister, to oversee rescue efforts. Environmental clean-up crews attempted to contain the oil spill that stretched 50 miles down the Yenisei River and killed 400 tons of fish at trout farms. Over two weeks, 2000 rescuers removed 177,000 cubic feet of debris, pumped 73 million gallons of water and pulled 14 survivors from the wreckage. But 75 workers–those trapped in the turbine hall and in the flooded rooms below–weren’t so lucky.

For Russians, the catastrophe called to mind the 1986 disaster at the Chernobyl Nuclear Power Plant in Ukraine, which was then part of the Soviet Union. Speaking on a Moscow radio station, Shoigu called the hydro dam accident “the biggest man-made emergency situation [in] the past 25 years–for its scale of destruction, for the scale of losses it entails for our energy industry and our economy.” Some commentators have called the events at Sayano-Shushenskaya the “Russian Chernobyl.” And just as Chernobyl raised questions globally about nuclear safety, Sayano-Shushenskaya has made other nations wonder: Are other hydropower plants at risk?


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Before: The turbine hall housed 10 640-megawatt turbines. Normally, 12 people manned the hall, but because of repair work, 115 people were on site on the day of the accident.

THE INVESTIGATION

Immediately after the accident, Russia’s Federal Service for Ecological, Technological, and Nuclear Supervision (Rostekhnadzor) launched an investigation. The official report, released on Oct. 3, blamed poor management and technical flaws for the accident.

According to the report, repairs on Turbine 2 were conducted from January to March 2009, and a new automatic control system–meant to slow or speed up the turbine to match output to fluctuations in power demand–was installed. On March 16, the repaired turbine resumed operation. But it still didn’t work right: The amplitude of the machine’s vibrations increased to an unsafe level between April and July. The unit was taken offline until Aug. 16, when the Bratsk fire forced managers at Sayano-Shushenskaya to push the turbine into service.

Back in operation, Turbine 2 vibrated at four times the maximum limit. As the control system decreased the turbine’s output on the morning of Aug. 17, the vibrations increased. The unit acted like the engine of an automobile being downshifted on a hill, shuddering violently and stressing the fatigued metal pins holding it in place. LMZ, the St. Petersburg metalworks that manufactured the plant’s turbines, gave the units a 30-year service life. Turbine 2’s age on Aug. 17 was 29 years, 10 months. Investigators determined that the power failure after the initial explosion had knocked out the safety system that should have shut down the plant–and a malfunction turned into a catastrophe.

Officials from RusHydro and the government have called for more stringent oversight of hydropower plants, but economic pressures may still put financial considerations ahead of safety. Six days before rescue efforts were halted on Aug. 29, repairs at Sayano-Shushenskaya were already underway. Rebuilding will take five years and cost approximately $1.3 billion–but a pair of nearby aluminum smelters, property of global aluminum giant RusAl, can’t wait that long. They consumed 70 percent of the station’s output and need replacement power to maintain production. RusAl and RusHydro are pressing the government for additional financing to accelerate completion of a joint venture at Boguchansk on the Angara River, now in its 29th year of construction.


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After: In the wake of the accident, 2000 rescuers removed debris, pumped water out of the flooded turbine hall and searched for survivors.

COULD IT HAPPEN HERE?

The U.S. has an installed capacity of nearly 100 gigawatts and an annual production of 250 terawatt-hours, which make it the world’s fourth largest hydroelectric producer. Yet even with a water-power history dating back to the 19th century, and more than 2000 such plants in operation, the U.S. has never had an event to match Sayano-Shushenskaya.

Experts agree that a similar accident is unlikely to occur here because American equipment is held to more stringent performance standards and rigid inspection regimes. The Bureau of Reclamation manages 58 hydropower plants, which produce 44 billion kilowatt-hours per year. Dan Drake, chief of the Hydraulic Equipment Group, the unit responsible for upkeep at iconic Western dams like Hoover, says bureau turbines are taken offline at the first sign of abnormal performance, and redundant automatic systems are in place. “If a unit were experiencing violent or abnormal vibrations,” Drake says, “it would shut down, and the gate at the top of the penstock would close.” Regular equipment repairs and replacement also keep dams safe.

Russia’s immediate solution to its power problem is to build more dams, but that won’t fix a bureaucratic culture that seems to devalue safety. “If they were running a turbine with known deficiencies, in essence, they’re putting economic concerns before human-life safety factors,” says Eric Halpin, the special assistant for dam and levee safety for the U.S. Army Corps of Engineers, America’s largest hydropower operator. “The principles we use are just the opposite. If it’s not safe, if there’s a risk of failure, all other benefits–be they economic, environmental or anything else–those all go away.”

ANATOMY OF A TURBINE FAILURE

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The photograph above, of the Sayano-Shushenskaya hydroelectric power plant, located 2000 miles east of Moscow in Siberia, was taken after the Aug. 17, 2009, accident that destroyed a section of the 950-foot-long turbine hall (circled in white). Water from the Yenisei River flows through 620-foot-long penstocks to power 10 turbines, which generate up to 6400 megawatts. Turbine 2 had been offline until the previous night, when it was brought online to compensate for energy lost because of a fire at another plant. Here’s how the disaster unfolded.

1—Fatigued by vibration, Turbine 2’s fastening pins break at 8:13 am. Water rushing down the penstock forces the 1500-ton unit through the turbine-hall floor and 50 feet into the air.


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2—A geyser of water flowing at 67,600 gallons per second destroys the roof and floods the turbine hall. Power outages occur and communication systems fail.

3—The automated safety system also fails. Turbines 7 and 9 continue to operate even though they are submerged, causing short circuits, explosions and structural damage.

4—Employees close the intake gates at the top of the dam at 9:30 am, and the immediate crisis ends. In the following days, 14 people are rescued from the debris; 75 lose their lives.


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