Turning Sand to Stone

Bacillus pasteuri, naturally occurring bacteria, can be used to turn sand into sandstone (calcite cement). This relatively simple process creates durable, low cost building materials. The technical name for this is microbial-induced calcite precipitation (MICP). Ginger Krieg Dosier of the United Arab Emerites was awarded the Metropolis 2010 Next Generation Winner for her innovative work. “If Dosier’s biomanufactured masonry replaced each new brick on the planet, it would reduce carbon-dioxide emissions by at least 800 million tons a year. Don’t bake the brick – grow it.”

From the above article: “Here are 12 simple steps for reproducing Dosier’s competition-winning idea. 1. Place the formwork in the sand. 2. Fill it up. 3. Level. 4. Shake the bacteria solution. 5. Pour it over the sand. 6. Let it saturate. 7. Pour the cementing solution over the sand. 8. Let it saturate. 9. Watch the brick harden. 10. Remove the formwork. 11. Watch the brick harden some more. 12. Behold, an ecobrick!”

Magnus Larsson: Turning Dunes into Architecture

Magnus Larsson, an architecture student who’s researching applications for MICP explains his proposed 6,000 kilometer habitable wall across Africa using bacteria-solidified sand in this TED talk.

Benefits of MICP stabilized earthbags include:
– stronger, more earthquake and hurricane resistant structures
– possibly thinner walls
– more durable water-resistant walls
– less tamping/faster construction
– less use of cement

Hurdles remain, however. The process gives off ammonia and so Dosier continues her research.

Magnus Larsson dune architecture

Image credit Magnus Larsson
The Better Brick: 2010 Next Generation Winner
Bio-Soil Improvement Their research involves stabilizing soils under the foundation.
Magnus Larsson.com
BLDG Blog
Big thanks to Scott Howard of Earthen Hand for alerting me to this concept.

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Ultra-High Performance Concrete

Ultra-High Performance Concrete

“According to a recent article in the Economist, Iran happens to be good, very good, at developing what is known as “ultra-high performance concrete” (UHPC). Because of its geographical position, the county is under constant threat of earthquakes. The most devastating earthquake in recent memory occurred in the city of Bam, located in southern Iran, and claimed the lives of 30,000 people. As a result, Iranian engineers have developed – out of necessity – some of the toughest and most rigid building materials in the world.

So how does Iranian concrete standout? Well, unlike conventional concrete, Iranian concrete is mixed with quartz powder and special fibers – transforming it into high performance concrete that can withstand higher pressure with increased rigidity. What this all translates to is excellent building material given the environment that has found peaceful applications like the construction of safer bridges, dams, tunnels, increasing the strength of sewage pipes, and even absorbing pollution.”

Read the full article at the source: Digital Trends.com

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