When I was a small and intensely young person, my parents would drive me down the California coastline to a town called Carmel near Monterrey Bay, where we would hang out on the beach and frolic amongst the slowly rotting kelp and aggressive sea gulls, eat burgers at Flaherty’s Seafood Restaurant (which specializes in seafood, not land food – I was five), and weave in and out of various art galleries until we were tired enough to return to our hotel and fall asleep.

Image courtesy citi-data.com

One time down in Carmel we saw an elephant seal carcass that had washed up on the beach, and on another occasion we passed two wealthy teenage girls furtively snorting cocaine out of a makeup compact as the sun set over the waves.

When I think about Monterrey, I tend to remember those childhood trips or to think about giant kelp and playful otters; coral reefs don’t immediately spring to mind. But Stanford University biomineralization expert Brent Constantz is working to change that with a new demonstration plant in the Bay that works just like a coral reef … but that manufactures cement.

Image courtesy sophiarogge.blogspot.com

Though tiny, “corals are the master builders of the animal kingdom. Powered on plankton and their symbiotic algae, hard corals extract the carbon dissolved in seawater and turn it into their calcium carbonate skeletons” (Guy). These skeletons build up on each other on a massive scale over time, creating rich habitat for diverse sea life that reminds me of what happens when we build cities out of concrete.

Image courtesy Calera.com

Constantz saw the opportunity to learn from nature and developed a coral-inspired cement manufacturing process. Cement manufacturing is a massive source of carbon emissions: in fact, “the cement industry is responsible for 5% of global carbon emissions, with each ton of cement producing a ton of CO2” (Guy). Constantz’s company, Calera, aims to green the production of cement by “capturing flue gases from factories, running them through a saline solution, and using electricity to convert the gases into solids. For 542 million years, corals have been sequestering carbon dissolved in water” (Guy). Calera is looking to reduce the time scale for sequestering carbon dioxide gas that could be affecting our climate.

WU XING:

I have filed this coral-like material under Earth and Water; connect the dots!

Cited:

Earthsky.org “Making Cement the Way Coral Does: Out of Thin Air.” Fastcompany.com Accessed 12/08/11. URL.

Guy, Allison. “Growing Cement like Coral.” NextNature.com 05/12/11. Accessed 12/08/11. URL.

D’Aulaire Drawing of Athena

This and all subsequent images courtesy Träullit

Woodwool cement may sound a little odd, but the name perfectly describes the product: it’s wood fiber (in this case, more specifically, Spruce) that looks like tangled wool fibers, and which is bound together with cement.  The manufacturing process is relatively simple: wood slivers are cut from logs, mixed with water and cement, and put in molds to set into shape. Wood fiber gives the product a heat-insulating, heat retaining and sound-absorbing properties. The cement binder provides strength, moisture resistance and fire protection.

According to the product data, woodwool evens out humidity levels in spaces where it’s installed by “absorbing moisture from or emitting moisture to the ambient air. This contributes to a pleasant indoor climate which is good for both comfort and health. The high pH value also discourages mould and the material is not affected by rot” (Träullit).  The woodwool panels also store heat from the ambient air and emit it when the air temperature falls, presumably due to an increase in the thermal mass of the wall systems to which they are applied.  If that is true, installing the panels could lower energy costs and reduce environmental impact. I like the idea that applying an inert material to the walls could affect indoor air quality – I have an utterly miserable dehumidifier in my apartment and it’s a noisy energy hog with only one function.

Woodwool panels contribute to the quality of the indoor environment in so many ways: the open cell material structure reduces reflection of sound, dampening noise and contributing to “restful acoustics in residential buildings, industrial premises and public spaces” (Träullit).  Another aspect of this product that I love is the fact that you can vacuum the panels to clean them, and they don’t emit dust or particulate matter.

FORM US WITH LOVE came up with a hexagonal panel design that “complements the practicality of the material, creating a simple but striking product” (Träullit).  They plan to introduce new shapes and colors every year, and you can order the 2011 collection now.  The 19 x 21cm  hexagons come in a range of earthy colours with nature-inspired names: cloud, moss, leaf, sky and stone.

Träullit Dekor panels are designed to attach to your walls magnetically.  The tiles are supplied with magnets affixed to the back, and adhere to thin metal sheets that are applied to the wall surface.  They can be fixed by hand and rearranged at any time.  They can also be fitted to walls with screws or glue. Check out their website where you can play with a nifty little tool that will let you design your wall!

WU XING:

I have filed woodwool cement board under wood and earth.

Cited:

http://www.traullitdekor.se/

I bring this up because tasting good (to other people, at least) is a positive characteristic of oysters.  Another positive trait is their uncanny ability to filter dirty nastiness out of rivers and bays, clarifying the water in which they dwell alongside myriad other creatures.  But from an architect’s standpoint, the most superlative characteristic of an oyster has to be its ability to stick itself to fellow oysters and riverbeds, enabling the formation of complex, long-lasting reefs.  These large oyster accumulations provide habitat for other species and protect the coastline from the ravages of storms.  And until recently, human beings had no clear idea exactly how oysters accrete to one another.

Image courtesy www.seattlemet.com

Image courtesy www.climateshift.org

At Purdue University, a research team has conducted experiments to discover the unique properties and composition of oyster cement, a “biomineralized adhesive material for aggregating into large communities.  This cement is an organic-inorganc hybrid and differs from the surrounding shells by displaying an alternate CaCO₃ crystal form, a cross-linked organic matrix, and an elevated protein content … the high inorganic content is exclusive to oysters” (Burkett et al).  If your eyes began to cross while reading the previous quote, have someone slap you on the back, have a shot of espresso, and stay with me. 

Image copyright Burkett, et al. Department of Chemistry and School of Materials Engineering, Purdue University

The researchers cut small sections through oyster shells  that had attached to each other via a small band of gray material that was still visible between the shells.  They pulverized samples of the outer shell, the gray material (oyster cement) and the inner shell of the oysters, and subjected each type of powder to various tests.  They dehydrated it, they treated it with acid, and they used Infrared (IR) spectroscopy among other means to determine that, in fact, the inner shell and outer shell of the oysters were compositionally distinct from the oyster cement.  Further, “the researchers were able to determine that the adhesive contained almost five times the amount of protein than what is found in the shell, as well as both iron and highly oxidized, cross-linked proteins” (Materials Technology).  Aaaand boom goes the dynamite!

What this means is that the oyster adhesive is more inorganic than your typical hydrated, organic glue-like material produced by mussels and barnacles (which are, admittedly, quite strong).  Those adhesives are composed mainly of proteins whereas oyster adhesive consists of about 90 percent calcium carbonate (chalk).  When I looked into calcium carbonate on the interwebs, I found out that the substance is crazy commonplace all over the globe – it’s found in all kinds of shells, most rocks, and even snails. 

It’s thought by the Purdue research team that what makes the oyster cement so effective is the interaction between the calcium carbonate and the small amount of protein that binds everything together.  They’re planning to “investigate the interaction of the different components within oyster cement and use this information for developing new synthetic materials” (Materials Technology).   If they can unravel the inner workings of oyster cement they’ll be able to “provide blueprints for the design of biomimetic materials, aid development of adhesion-inhibiting antifouling surfaces, and illustrate the workings of healthy ecosystems” (Burkett et al).  It’s exciting to think that we could be on our way to developing adhesives for use in medicine and construction that set and hold in wet environments.

*Do oysters even have eyes?? Gross.

Image courtesy www.content.cdlib.org

WU XING:

I am filing oyster cement under water (heh – get it!) and also in the earth category because you can basically make land if you have enough oysters.  The Purdue paper mentioned that some reef structures are “tens of meters deep and several square kilometers in area” (Burkett et al).

Cited:

Burkett, Jeremy R., Lauren M. Hight, Paul Kenny, and Jonathan J. Wilker. “Oysters Produce and Organic-Inorganic Adhesive for Intertidal Reef Construction.”  Journal of the American Chemical Society, 2010. Volume 132, pages 12531-12533.

“Oysters Offer Clues to New Adhesive Materials” Materials Technology @ TMS. 09/23/10.  Accessed 10/05/10.  URL.