Quotes: MENA   Enter Symbol: NewsLetter: Search: advanced

New method to remain safe during quakes applauded  Join our daily free Newsletter

MENAFN - Arab News - 22/02/2014
No. of Ratings : 0
Add to Mixx!



(MENAFN -Arab News) THE “earthquake” was seconds away. The floodlights were on. The cameras and the sensors were ready


All eyes were on the eight-foot, two-ton section of a Washington National Cathedral pinnacle that stood like a missile in the Columbia University engineering laboratory


It was the biggest object ever tested on the lab’s shake table. (The table can hold three tons, or 6,000 pounds.) The plan was to see whether a steel reinforcing rod screwed through the middle would hold the limestone sections together


Shortly before noon, a warning buzzer sounded. A blue emergency light began flashing, and the crowd of student bystanders put on their hard hats


Lab director Adrian Brugger announced that the quake was about to begin


“And, start,” he said


The metal table on which the pinnacle was bolted began to jerk back and forth, squeaking as it did. There was no rumbling. No falling debris


No one fleeing into the streets


It lasted 30 seconds. Brugger turned from a bank of computer screens and said, “That’s it.” The room was silent. That was it? Yes, he said, that was it. Applause broke out


Last week, an earthquake similar to the 5.8-magnitude quake that struck the Washington area in August 2011 was simulated in New York City. But it was in a laboratory. There were no injuries, and the whole thing was sort of underwhelming


The simulation was a success, though. The steel rod held the pieces of the test pinnacle firmly together. There was nary a crack in the stone or the mortar


“Well, there you have it,” said Joe Alonso, the cathedral’s head stonemason, who had helped put the test together and was watching. “I’m glad what we didn’t see. We saw it on Aug. 23, 2011. That was enough for me.” “It’s not very interesting,” said George Deodatis, chairman of Columbia’s Department of Civil Engineering and Engineering Mechanics. “But this is how the earthquake occurred.&rdquo


He said the engineers thought about adding some low-frequency noise to the test for effect. “But we’re not Hollywood,” he said. “We’re scientists.&rdquo


The real earthquake, on a Tuesday afternoon, rattled the 301-foot-tall Episcopal cathedral in Northwest Washington to the tips of its majestic towers. Gargoyles, crockets and huge stone finials shook loose and came crashing down


The quake knocked off the top of the southwest pinnacle on the cathedral’s central tower. The pinnacle fell on the cathedral roof, and the shaking nearly knocked over the tops of three other pinnacles, which were within seconds of falling


All loose or dislodged stone was subsequently removed from the structure, which suffered millions of dollars in damage. Full repairs are expected to take years


The stones of the old pinnacles had been held together with small bronze dowels, Alonso said. As earthquake repairs proceeded on the English Gothic-style cathedral, experts realized they needed a better system of reinforcement


The steel rod seemed to be the answer


Alonso, who has been immersed in the cathedral’s repairs since the quake, said he thought that it worked


“That rod that’s in there, the way we screwed it down, I would imagine that did what it was supposed to do,” he said. “Without that rod, if that was doweled together with those little bronze dowels . . . there’s no doubt this thing would have come apart just like they did in the quake.&rdquo


As for the simulation, Deodatis said it was difficult to replicate exactly what was experienced at the cathedral, almost 100 miles from the quake’s epicenter near Mineral, Virgini


The Columbia engineers came up with a good estimate and then bumped the intensity up a notch. “It’s very close to what happened that day,” Deodatis said


The test, which cost about 45,000, was about a year in the making, Alonso said


It was largely arranged by longtime cathedral consultant Robert Mark, a professor emeritus of architecture and civil engineering at Princeton University. Mark and Deodatis were colleagues at Princeton


Mark, who was present at the test, said an early plan had been to place a model of the entire cathedral on the shake table. But he realized that a model would not generate the data they wanted


“We decided it’s better to do it at full scale because we wanted to check how the stone and the mortar stood up,” he said


To set up the test, Alonso ordered five pre-cut limestone pieces from the same quarry in Indiana that provided stone for the construction of the cathedral. He and other cathedral stonemasons then assembled the pieces into a rough copy of the pinnacle section that fell


Last month, the disassembled pieces were trucked to Columbia, and this month, Alonso and his men reassembled them in the Columbia laboratory and fastened them together with the rod


“The intent was . . . to simulate as close as possible the finished and fully re-created pinnacle that’s going to go back up on the central tower,” said James W. Shepherd, the cathedral’s director of preservation and facilities


The test piece won’t be used in a new pinnacle, Alonso said, but the stone will be recycled


The test included two other simulated earthquakes, a lesser shake and a more severe shake. The pinnacle structure was sound throughout


After the tests, Alonso and Deodatis used magnifiers to examine the surface of the stone for cracks


“It’s in perfect condition,” Deodatis said at one point. “You’re absolutely safe.&rdquo


He added later: “I would stand next to this during an earthquake.&rdquo


“You can’t get a better guarantee than that,” Mark said.


 


Arab News




  MENA News Headlines
 Jan 28 2015 - Gulf states to rethink monetary policyMENAFN
(MENAFN) Gulf Arab oil states may need to rethink longstanding economic policies, including their fixed exchange rates, over the next five to 10 years as economic cycles in the region and the US ...

 Jan 28 2015 - DIB picks arrangers for potential Tier 1 sukukKhaleej Times
(MENAFN - Khaleej Times) Dubai - Dubai Islamic Bank, or DIB, said on Tuesday that it picked eight banks to arrange roadshows from January 8 for a potential benchmark size dollar-denominated sukuk ...

 Jan 28 2015 - What next for Londonium and Barclays?Khaleej Times
(MENAFN - Khaleej Times) I have tried to visit Britain on the eve of every general election since the end of the Thatcher era (by Tory regicide, not the ballot box) in November 1990 in search of ...

 Jan 28 2015 - Emirates NBD - holding the banking fortKhaleej Times
(MENAFN - Khaleej Times) The banking industry looks set to sustain positive trends this year due to strong macroeconomic economic indicators, sufficient liquidity and low interest rates in the ...

 Jan 28 2015 - China pumps cash into banks in a bid to accelerate growthKhaleej Times
(MENAFN - Khaleej Times) Beijing - China's central bank has bolstered support for the cooling Chinese economy by injecting another 50 billion yuan ($8.1 billion) worth of short-term loans into banks ...

 Jan 28 2015 - Union National Bank posts 16% jump in annual earningsKhaleej Times
(MENAFN - Khaleej Times) People walking past a Union National Bank branch in Dubai. The total assets of the UNB Group increased by seven per cent in 2014 to Dh93.5 billion as at December 31, 2014. - ...

 Jan 28 2015 - Gulf Arab countries may need to rethink policy: Qatari bankerKhaleej Times
(MENAFN - Khaleej Times) Dubai - Gulf Arab oil states may need to rethink longstanding economic policies, including their fixed exchange rates, over the next five to 10 years as economic cycles in ...

 Jan 28 2015 - GCC retail sector on growth pathKhaleej Times
(MENAFN - Khaleej Times) Dubai - GCC retail sales are expected to grow at a 7.3 per cent compound annual growth rate (CAGR) between 2013 and 2018 to reach $284.5 billion, according to Alpen ...

 Jan 28 2015 - Dubai International airport crowned as world's busiestKhaleej Times
(MENAFN - Khaleej Times) The airport's passenger numbers boosted by 6.1 per cent to 70.5 million in 2014 and pushed the Heathrow down to the second position as London's top airport handled 68.1 ...

 Jan 28 2015 - Sharjah's Dh17.7b budget to ensure economic upliftKhaleej Times
(MENAFN - Khaleej Times) Sharjah - His Highness Dr Shaikh Sultan bin Mohammed Al Qasimi, Member of the Supreme Council and Ruler of Sharjah, on Tuesday approved the 2015 general budget of the emirate ...

more...


 






Google

Electronic & Mobile Payment

 
 

Middle East North Africa - Financial Network

MENAFN News Market Data Countries Tools Section  
 

Middle East North Africa - Financial Network
Arabic MENAFN

Main News
News By Industry
News By Country

Islamic Finance News
Private Equity News

How-To Guides
Technology Section

Travel Section

Search News

Market Indices
Quotes & Charts

Global Indices
Arab Indices

Commodoties

Oil & Energy

Currencies Cross Rates
Currencies Updates
Currency Converter

USA Stocks
Arab Stocks
 

Algeria 
Bahrain 
Egypt 
Iraq
Jordan 
Kuwait 
Lebanon
Morocco 
Oman 
Palestine
Qatar 
Saudi Arabia 
Syria
Tunisia 
UAE 
Yemen

Weather
Economic Calendar
Financial Glossary


Financial Calculators

RSS Feeds [XML]

Corporate Monitor

Events

Real Estate
Submit Your Property

Arab Research
Buy a Research

Press Releases
Submit your PR

Join Newsletters


 
© 2014 menafn.com All Rights Reserved.  Terms of Service | Privacy Policy | Contact Us | Advertise | About MENAFN | Career Opportunities | Feedback | Help