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Wooden skyscrapers could be the future of flat-pack cities around the world

When American engineer William Le Baron Jenney designed the world’s first skyscraper in Chicago in 1884, no one believed in his unconventional technologies. His lightweight steel frame relieved a structure of its heavy masonry shackles, enabling it to soar to new heights. Perplexed by this trade-in of solid brick for a spindly steel skeleton, Chicago inspectors paused the construction of the Home Insurance Building until they were certain it was structurally sound.

Of course, Jenney’s revolutionary edifice provided a blueprint for city skylines across the world. By 2011, China was reckoned to be topping off a new skyscraper (500ft or taller) every five days, reaching a total of 800 by 2016. Toronto, now North America’s fourth largest city, currently has 130 high-rise construction projects under way.

As a result, buildings are slowly choking the atmosphere. In Britain, where the construction industry accounts for almost 7% of the economy (including 10% of total employment), 47% of greenhouse gas emissions are generated from buildings, while 10% of CO2 emissions come from construction materials. Furthermore, 20% of the materials used on the average building site end up in a skip.

So just as Jenney’s steel-frame solved the issue of the dense, stunted buildings in the 19th century, architects and engineers are now seeking new ways of building taller and faster without having such a drastic impact on the environment. And that has seen them revisit the most basic building material of them all: wood.

Although wood in its raw form could not compete with Jenney’s steel-frame wonder, a type of super-plywood has been developed to step up to the challenge. By gluing layers of low-grade softwood together to create timber panels, today’s “engineered timber” is more akin to Ikea flat-packed furniture than traditional sawn lumber, and offers the prospect of a new era of eco-friendly “plyscrapers”.

For Vancouver-based architect Michael Green, the sky is the limit for wooden buildings. While nearing completion of the University of Northern British Columbia’s Wood Innovation and Design Centre in Prince George, Green’s practice, MGA, has also drawn up plans for a 30-storey, sun-grown tower for downtown Vancouver.

If built, Green’s vision would be easily the world’s tallest wooden building, soaring past the current contenders – London’s Stadthaus at nine storeys, and the 10-storey Forte Building in Melbourne. But that’s not the main motivation, according to MGA associate Carla Smith. “To be honest, it’s not like we really care about being the tallest,” she says. “We really do see a wooden future for cities, and our aim is to get others to jump on board too.”

The Nelson Marlborough Institute of Technology arts and media building under construction in Nelson, New Zealand

Green is giving away his hefty, 200-page instruction manual, The Case for Tall Wood Buildings, free of charge. He hopes it will inspire architects and engineers to branch out beyond their concrete and steel confinements, and embrace a material that sequesters carbon dioxide from the atmosphere, holding it captive during its growth and lifetime in a structure – one tonne of CO2 per cubic metre of wood. To put that in context, while a 20-storey wooden building sequesters about 3,100 tonnes of carbon, the equivalent-sized concrete building pumps out 1,200 tonnes. That net difference of 4,300 tonnes is the equivalent of removing 900 cars from the city for a year.

But while timber advocates such as Green hope to to sow the seeds of change in the minds of policymakers worldwide, building regulations still put a low-rise lid on the height of timber buildings. This is based on wood’s historic reputation as kindling for a great city fire: in London, Chicago and San Francisco (to name just a few), roaring fires have ravaged city streets, wiping out great swathes of grand architecture and razing urban history to the ground. But while the classic timber-framed city of 1870s Chicago was gone in an instant, today’s engineered timber develops a protective charring layer that maintains structural integrity and burns very predictably – unlike steel, which warps under the intense heat.

The rigidity of mass timber panels has tended to restrict architects to a “house of cards” design, whereby panels are slotted together and stacked on top of one another in repetitive patterns. But new innovations are coming thick and fast: the USDA recently announced a $2m investment for wood innovation, and in the previously scorched city of Chicago, mega-firm Skidmore, Owings and Merrill published a study that re-imagines the 42-storey Dewitt Chestnut apartment block as a timber tower. In Europe, a 14-storey wooden building is currently under construction in Bergen, Norway, with another eight-storey structure on its way up in Dornbirn, Austria – the prototype for a 20-storey plyscraper designed by the global engineering firm Arup.

The finished NMIT arts and media building

One other important breakthrough came in British Columbia, a Canadian province half-covered in forest. Since 1996, more than 16m hectares have been destroyed by North America’s native mountain pine beetle, which releases a blue-staining fungus into the wood, halting the flow of nutrients and water and the killing the tree.

The province faced the prospect of billions of these dead lodgepole pines triggering a huge release of carbon dioxide – until a means of using this undesirable blue-stained lumber for building was realised. British Columbia promotes its use through the Wood First Act, passed in 2009, which requires all new, publicly financed construction projects to first consider wood as the primary building material.

The most prominent example is Vancouver’s 2010 Winter Olympic ice rink, the Richmond Oval, which features massive glued-laminated timber arches of beetle-ravaged wood. Building regulations are now loosening up in Canada, reflecting the recent successes of the country’s wood use. Last month, Ontario raised the cap on timber structures from four storeys to six, just as British Columbia did in 2009.

But perhaps the most promising realisation of wood’s worth is in New Zealand, where the violent earthquakes of 2010 and 2011 left almost one third of the Christchurch’s buildings – including 220 heritage sites – up for demolition. Almost four years on, the city’s grand rebuild has begun, and wood has taken a step into the spotlight due to its durability in high-seismic activity zones. The “new” Christchurch, as outlined in the Central Recovery Plan, is proposed to be a low-rise, “greener, more attractive” city costing around NZ$40bn (£19bn), almost 20% of the country’s annual GDP.

A detail of the Merritt building in Christchurch’s central business district Photograph: PR

Andrew Buchanan, professor of timber design at the University of Canterbury, sees a growing interest in the use of wood in Christchurch’s rebuild. “When it first happened, people were scared of concrete and masonry buildings,” he says. “Wood was seen as a very desirable and very safe alternative.”

Earlier this year, Christchurch welcomed its first post-earthquake, multistorey timber structure – the Merritt building in the city’s central business district. The structure uses a “post-tension” technology – the brainchild of Buchanan and his colleagues – where timber is lashed together with steel tendons that act like rubber bands, allowing the building to snap back into place following any seismic movement. And recently, the Southern Hemisphere’s first engineered timber factory opened up in Nelson, producing timber panels for flat-pack cities across the globe.

In China, Arup is currently working to educate engineers on the use of wood. With even a superfirm like SOM – the architects behind One World Trade Center and the Burj Khalifa – considering using of wood for high-rise construction, the industry finally appears ready to grasp its full potential.

Several of SOM’s buildings are in Chinese cities (the 71-storey Pearl River Building in Guangzhou, and the 88-storey Jin Mao in Shanghai, for example), so perhaps their Timber Tower could take root there too? “Judging from the speed that the Chinese usually adopt new technologies,” says Arup director Tristram Carfrae, “this really won’t take very long!”

Source: www.theguardian.com

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Planet Earth

Once a Year at 11:11 am the Sun Shines Perfectly on this Memorial

At precisely 11:11 a.m. each Veterans Day (Nov. 11), the sun’s rays pass through the ellipses of the five Armed Services pillars to form a perfect solar spotlight over a mosaic of The Great Seal of the United States.

The Anthem Veterans Memorial, located in Anthem, Arizona, is a monument dedicated to honoring the service and sacrifice of the United States armed forces. The pillar provides a place of honor and reflection for veterans, their family and friends, and those who want to show their respects to those service men and women who have and continue to courageously serve the United States.

The memorial was designed by Anthem resident Renee Palmer-Jones. The five marble pillars represent the five branches of the United States military. They are staggered in size (from 17 ft to 6 ft) and ordered in accordance with the Department of Defense prescribed precedence, ranging from the United States Army, the United States Marine Corps, the United States Navy, the United States Air Force and the United States Coast Guard.

Additionally, the brick pavers within the Circle of Honor are inscribed with the names of over 750 U.S. servicemen and women, symbolizing the ‘support’ for the Armed Forces. The pavers are red, the pillars are white, and the sky is blue to represent America’s flag. The circle represents an unbreakable border. Anthem resident and chief engineer, Jim Martin was responsible for aligning the memorial accurately with the sun.

Awards

– Arizona Historic Landmark Designation 2012 – Arizona Historical Society
– Arizona Public Works Project of the Year Award 2012 – Arizona Chapter of the American Public Works Association
– ACEC 2012 Grand Award – Best Engineering and Environmental Consulting Project

Sources

– Anthem Community Council
– Arizona Tourism: Anthem Veterans Memorial
– ABC Arizona: Anthem dedicates memorial to veterans

Anthem Veterans Memorial

41703 N. Gavilan Peak Parkway
Anthem, AZ 85086
(623) 742-6050

Veterans Day is an official United States holiday that honors people who have served in the U.S. Armed Forces, also known as veterans. It is a federal holiday that is observed on November 11. It coincides with other holidays such as Armistice Day and Remembrance Day, which are celebrated in other parts of the world and also mark the anniversary of the end of World War I (major hostilities of World War I were formally ended at the 11th hour of the 11th day of the 11th month of 1918, when the Armistice with Germany went into effect).

The United States also originally observed Armistice Day; it then evolved into the current Veterans Day holiday in 1954. Veterans Day is not to be confused with Memorial Day; Veterans Day celebrates the service of all U.S. military veterans, while Memorial Day is a day of remembering the men and women who died while serving. [source]

SOURCE: alien-ufo-sightings.com

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Could Earth Have Been Seeded With Life?

How did life begin? The biggest question mankind has asked itself.  Where did we come from? The idea that gods from the heavens had provided the seed of life has been supported by many researchers. End of the day we may have been looking into the correct direction: a breakthrough study claims that the so-called building blocks of life, the elements that are the backbone of organic molecules which form living matter, came to Earth from outer space.

Evidence of seeding

According to a team of researchers from the University of Hawaii at Manoa and their colleagues from France and Taiwan, phosphates and diphosphoric acid, two major chemicals that form chromosomes carrying our genetic information, were generated billions of kilometers away from our planet and were delivered to Earth by space wanderers such as asteroids or comets.

The scientists used a vacuum chamber cooled down to near absolute zero to simulate interstellar icy grains coated with carbon dioxide, water, and phosphine.

When exposed to radiation, these grains created both phosphates and diphosphoric acid. “On Earth, phosphine is lethal to living beings,” said Andrew Turner of the University of Hawaii.

“But in the interstellar medium, an exotic phosphine chemistry can promote rare chemical reaction pathways to initiate the formation of biorelevant molecules such as oxoacids of phosphorus, which eventually might spark the molecular evolution of life as we know it.”

Scientists suggested that these phosphorus oxoacids could be traced back to an interstellar medium, the materials that fill the space between stars, which are delivered to Earth by comets or meteorites.

Panspermia is a mechanism that allows biology to spread through space without needing a spaceship. Living matter “hitches a ride on sunlight or inside rocks.” Some scientists believe that Mars was indeed inhabited at one time. Some space rocks were “kicked” off the planet and landed in a “suitably welcoming patch” on Earth. Biological material from Mars that was in the rocks may spur exploration into the search for the solution to the age-old question: Where do we come from and why are we here? There are several theories that relate to extraterrestrials.

There are suggestions that aliens escape from an unknown planet and come here due to dire circumstances on their home planets and most likely we are descendants of this race.  Environmentalist and ecologist turned author Dr. Ellis Silver believes we may have come from Alpha Centauri. The planet may have suffered some type of cataclysmic event from which a few residents were able to escape and come to Earth.

Other scientists believe that, eons ago, Humanoids inhabited Mars but a war destroyed the livability of the planet. This could have been due to the equivalent of two hydrogen bombs exploding on Mars 300,000 to 1 million years ago. Is it possible some living beings were able to escape to Earth before the destruction?

There are many mysteries and controversial theories for which there seems to be more questions than answers.

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Rare T. Rex Relative Discovered in New Mexico

They don’t look remarkable to the untrained eye. The skull bones are fragmentary, unrecognizable to most. The story of a fearsome tyrannosaur, who lived millions of years before T. rex, would remain lost to the ages had it not been for the fossil’s discovery in New Mexico by a dedicated team of dinosaur hunters.

Digging in rock known to be approximately 80 million years old, but also infamous for its lack of fossil preservation, paleontologists Andrew McDonald, Douglas Wolfe, and their team searched for remnants of life in the Menefee Formation of New Mexico. This particular geologic formation was part of Laramidia, the western part of the ancient continent that eventually became the North America we know today.

Clues were there from the very beginning: Most of the bones were hollow and the skull segments were distinctive. Excited, McDonald knew these indicated a theropod. But what kind?

Theropods were bipedal dinosaurs and most, but not all, were carnivorous. Tyrannosaurus rex is the most well known type of theropod, but it’s just one of a very diverse group of animals. It is also a later form of tyrannosaur. Many of the T. rex fossils people recognize from museums are approximately 66 million to 77 million years old. Earlier forms of tyrannosaur are extremely rare.

In a paper published today, McDonald, Wolfe, and Alton Dooley Jr., introduce Dynamoterror dynastes, which is only the second known tyrannosaur in Laramidia from this time period. D. dynastes walked the Earth approximately 80 million years ago.

Comparing fragments of bones offers a unique challenge to paleontologists hoping to identify such fossils. It took considerable research into published data, as well as trying to match the bones with available specimens. Perhaps one of the most exciting aspects of the study was the use of 3D scanning and printing to facilitate their research.

3D models of the D. dynastes bones. Image: McDonald et al.

The two frontal bones of the skull of D. dynastes were broken in different ways, but there was enough on both sides that they could reconstruct them.

“There are features on the right frontal,” explained McDonald, curator at the Western Science Center, “that aren’t preserved on the left, and vice versa. But there are enough overlapping features” that enabled them to recreate a digital composite of both bones.

“Those overlapping features gave us landmarks to work with,” he said.

To be clear, Dooley, executive director of the Western Science Center, said, “the 3D modeling didn’t reveal any feature that we didn’t already know was there. But it made it much easier to make the comparisons and for us to interpret what we were looking at.”

What would have previously taken weeks to confirm their fossil interpretation took only three days with the 3D models.

“The whole process of producing the composite 3D model took us [approximately] a day to scan the fragments,” said Dooley, “then maybe one more day to make the composite model and then a third day to print it out.”

These scans are publicly available to download from Morphosource and Sketchfab, enabling anyone to use them for noncommercial purposes.

“We hope that [publicly available digital fossil scans] become the standard,” Dooley said. “It’s not going to replace looking at the original specimens. As good as scans are, the actual specimen is still better. But sometimes you don’t need the original specimen. You can get the data that you need perfectly well from just a scan.” He said that these digital scans open up fossil research to scientists who may be limited by time or money.

He added: “We’re not doing [scientific] work to keep it secret. We want to further human knowledge. We want other scientists to be able to use this specimen to help them in their own research. Travel is expensive; it can be difficult. And if we can do things to mitigate the costs of doing research, we can make it more accessible.”

Source gizmodo.com

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