Quotes: US 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
 Oct 23 2014 - Kuwait: 13 sentenced over speechArab Times
(MENAFN - Arab Times) KUWAIT CITY Oct 22 (Agencies): A Kuwaiti defense lawyer says a court in the Gulf nation has convicted and sentenced 13 people to two years in prison each for reading aloud a ...

 Oct 23 2014 - Kuwait- Trade cheats face lawArab Times
(MENAFN - Arab Times) KUWAIT CITY Oct 22 (KUNA): The Ministry of Commerce and Industry is taking it upon itself to strike with a firm hand any businesses that practice commercial fraud against ...

 Oct 23 2014 - Kuwait- Crown Prince chairs National Security Council sees dangerArab Times
(MENAFN - Arab Times) KUWAIT CITY Oct 21 (KUNA): His Highness the Crown Prince Sheikh Nawaf Al-Ahmad Al- Jaber Al-Sabah on Tuesday chaired the first meeting of the National Security Council with its ...

 Oct 23 2014 - test with imageABN Newswire
(MENAFN - ABN Newswire)   ...

 Oct 23 2014 - Saudi Almunajem acquires 25 percent stake in France's DouxMENAFN
(MENAFN) Almunajem, the Saudi-Arabian food group, announced it has acquired a stake of 25 percent in the Groupe Doux, the French poultry producer, Saudi Gazette reported.Almunajen is the main ...

 Oct 23 2014 - Oman's PSC net profit down 25.2 percent in 9MMENAFN
(MENAFN) Oman's Port Services Corporation (PSC) announced it has posted a decline in its net profit by 25.2 percent for the January-September period of this year due to the termination of major cargo ...

 Oct 23 2014 - Saudi's Al Tayyar profit up 13.5 percent in Q3MENAFN
(MENAFN) Saudi Arabia's Al Tayyar Travel Group announced it has posted an increase in its net profit, which increased by 13.5 percent during the July-September period due to an increase in the ...

 Oct 23 2014 - Dar Al-Arkan to invest USD267m on projects in 2015MENAFN
(MENAFN) Dar Al-Arkan Real Estate Development Co., Saudi Arabia's largest developer, announced it is planning to spend over USD267 million on projects next year as part of its plan to achieve a 10 ...

 Oct 23 2014 - UAE's Mazaya net profit hits USD in 9MMENAFN
(MENAFN) Al Mazaya Holding Company announced that it recorded a net profit of USD20 million in the January-September period of this year, compared to USD 2.920 million recorded during the ...

 Oct 23 2014 - Saudi Arabia's ACWA to focus on renewable energy projectsMENAFN
(MENAFN) ACWA Power, the Saudi Arabia-based power and water project developer, announced it is planning to secure financing for USD15 billion worth of projects, nearly half of which are in renewable ...

more...


 






Google

Click to Apply

 
 

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

IPO News
Islamic Finance News
Private Equity News

How-To Guides
Technology Section

Travel Section

Search News

Market Indices
Quotes & Charts

Global Indices
Arab Indices

US Markets Details

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
Investment Game
Economic Calendar
Financial Glossary

My MENAFN
Portfolio Tracker

Voting

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


 
© 2000 menafn.com All Rights Reserved.  Terms of Service | Privacy Policy | Contact Us | Advertise | About MENAFN | Career Opportunities | Feedback | Help