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Living Bio-Concrete Can Heal Itself

Concrete is the world’s most common building material, and a particularly long-lasting one. Concrete structures from the Roman Empire still stand today. But it’s not indestructible, and when this cement mixture cracks under pressure, it’s both dangerous and expensive to fix. Cracks in concrete allow in salt and water that can corrode the steel reinforcements inside. No one wants a bridge, high-rise, or dam to suddenly break apart.  

To make it easier to repair structures that are hard to access—in extreme environments, supertall skyscrapers, or underground—engineers are determined to create a concrete that can fix its own fissures through naturally occurring reactions.

One self-healing concrete prototype starts to work when exposed to sunlight. Another, developed by researchers at Delft University of Technology in the Netherlands, uses bacteria to mend its own cracks—no sun required. 

Bacillus bacteria are added to the concrete—a blend of cement, sand and water—during the mixing phase. The bacteria feed on capsules of calcium lactate that are water soluble. When moisture enters the concrete through a new crack, it opens up the capsules, allowing the bacteria to feed, germinate, and multiply, and in the process form limestone that fills the cracks. If the concrete remains whole and sealed, no water can get in, and the bacteria remain inactive. Since bio-concrete only needs moisture to work, it's well-suited to heal underground structures in dams, basements, and more. 

Bio-concrete might be particularly useful in China, which used more cement between 2011 and 2013 than the U.S. did in the whole 20th century

[h/t: reddit]

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Dan Bell
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Design
A Cartographer Is Mapping All of the UK’s National Parks, J.R.R. Tolkien-Style
Peak District National Park
Peak District National Park
Dan Bell

Cartographer Dan Bell makes national parks into fantasy lands. Bell, who lives near Lake District National Park in England, is currently on a mission to draw every national park in the UK in the style of the maps in J.R.R. Tolkien’s The Lord of the Rings, Kottke.org reports.

The project began in September 2017, when Bell posted his own hand-drawn version of a Middle Earth map online. He received such a positive response that he decided to apply the fantasy style to real world locations. He has completed 11 out of the UK’s 15 parks so far. Once he finishes, he hopes to tackle the U.S. National Park system, too. (He already has Yellowstone National Park down.)

Bell has done various other maps in the same style, including ones for London and Game of Thrones’s Westeros, and he commissions, in case you have your own special locale that could use the Tolkien treatment. Check out a few of his park maps below.

A close-up of a map for Peak District National Park
Peak District National Park in central England
Dan Bell

A black-and-white illustration of Cairngorms National Park in the style of a 'Lord of the Rings' map.
Cairngorms National Park in Scotland
Dan Bell

A black-and-white illustration of Lake District National Park in the style of a 'Lord of the Rings' map.
Lake District National Park in England
Dan Bell

You can buy prints of the maps here.

[h/t Kottke.org]

All images by Dan Bell

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The North Face
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Design
The North Face's New Geodesic Dome Tent Will Protect You in 60 mph Wind
The North Face
The North Face

You can find camping tents designed for easy set-up, large crowds, and sustainability, but when it comes to strength, there’s only so much abuse a foldable structure can take. Now, The North Face is pushing the limits of tent durability with a reimagined design. According to inhabitat, the Geodome 4 relies on its distinctive geodesic shape to survive wind gusts approaching hurricane strength.

Instead of the classic arching tent structure, the Geodome balloons outward like a globe. It owes its unique design to the five main poles and one equator pole that hold it in place. Packed up, the gear weighs just over 24 pounds, making it a practical option for car campers and four-season adventurers. When it’s erected, campers have floor space measuring roughly 7 feet by 7.5 feet, enough to sleep four people, and 6 feet and 9 inches of space from ground to ceiling if they want to stand. Hooks attached to the top create a system for gear storage.

While it works in mild conditions, the tent should really appeal to campers who like to trek through harsher weather. Geodesic domes are formed from interlocking triangles. A triangle’s fixed angles make it one of the strongest shapes in engineering, and when used in domes, triangles lend this strength to the overall structure. In the case of the tent, this means that the dome will maintain its form in winds reaching speeds of 60 mph. Meanwhile, the double-layered, water-resistant exterior keeps campers dry as they wait out the storm.

The Geodome 4 is set to sell for $1635 when it goes on sale in Japan this March. In the meantime, outdoorsy types in the U.S. will just have to wait until the innovative product expands to international markets.

[h/t inhabitat]

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