Good Thinking

Wool and seaweed makes bricks stronger

Wool and seaweed makes bricks ...
Bricks made for the Seville/Strathclyde study
Bricks made for the Seville/Strathclyde study
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One of the bricks being strength-tested
One of the bricks being strength-tested
Bricks made for the Seville/Strathclyde study
Bricks made for the Seville/Strathclyde study

In a collaborative study on sustainable building materials, researchers from Spain’s University of Seville and Glasgow’s University of Strathclyde have created bricks that contain sheep’s wool and a polymer derived from seaweed. Clay-based soils were provided by Scottish brick manufacturers, while the wool came from Scotland's textile industry, which produces more of the stuff than it can use. The polymer was an alginate, which occurs naturally in the cell walls of seaweed. Mixed together, the three substances resulted in bricks that were reportedly 37 percent stronger than regular unfired bricks.

“These fibers improve the strength of compressed bricks, reduce the formation of fissures and deformities as a result of contraction, reduce drying time and increase the bricks' resistance to flexion,” the study’s authors concluded.

The bricks are environmentally-friendly in that they are composed of sustainable, non-toxic, locally-available materials, and don’t require the expenditure of energy that goes into the firing of other types of bricks – it wasn’t mentioned, incidentally, how their strength compared to that of fired bricks.

One of the bricks being strength-tested
One of the bricks being strength-tested

The wool-and-seaweed bricks also don’t create the carbon dioxide that is generated by the production of Portland cement, which is an ingredient in most types of concrete. There is no word yet from Seville or Strathclyde on whether or not there are plans to produce the bricks commercially.

The research was recently published in the journal Construction and Building Materials.

Even more important than how they compare to fired bricks is their stability (water proof). Without cement or emulsified asphalt soil (adobe) bricks must be fired or they crumble quickly when subjected to moisture. This has been a worldwide problem for millenniums. Of course by \"quickly\" I mean after many decades. If a cheaper stabilizing agent can be found this will make building with soil in the poorer countries safe and within everyone\'s means. Shelters can be build locally by hand that last centuries.
I went to the link: Construction and Building Materials to read the complete article and found they charge $39.95. Too bad, I was curious.
"it wasn't mentioned, incidentally, how their strength compared to that of fired bricks." And it was not the job of the writer to do a little digging and find out how normal unfired bricks compare to normal fired bricks, thus answering the question. Research as a journalism skill has been replaced by re-packaging.
I can say that this "Development" is not relevant.
How many people in Scotland use Mud-bricks for dwellings...
With the climate It would be a guess to say "Not many"
The Wool, and Polymer used, are both Hydrocarbon based... (Same as Oil, and Plastics...) as all Hydrocarbons Degrade above 400 Degrees C, the actual "Composite nature of the Brick will be lost at the normal firing temperature of Bricks.. (~1300 Deg C)
This will leave voids in the Bricks, leading to possible failure at lower stress than the unreinforced brick... (Speculation all of it)
IF the Bricks are Fired in an Anaerobic (Noble gas or vacuum) environment the carbon in the Reinforcing may actually lead to increased fracture toughness.... Though it will be best to add it , not as Wool or Plastic, but as reduced carbon (nano-tubes, or fibre strands) in the laying up stage.... avoiding, "voids" in the fired brick.... Now if they can show a method to turn all of that Unused wool in Scotland into carbon fibre, they may be onto a winner, with cheaper methods of reducing CF for the Reinforced plastics industry, forget bricks....
The bible tells you how to make Strong Bricks, use the Egyptian Recipe from ca 1800 BC, (Exodus 5:7 even they knew that adding stuff to bricks made them stronger, (these were Mud bricks not fired bricks).
Gregg Eshelman
Just look at what happened to Bam, Iran to see how poor unfired bricks are as a construction material.
Heck, look at most any archaeology dig of ancient cities that were damaged or completely destroyed by earthquakes.
Designing a better unfired brick makes as much sense as designing a better buggy whip.
Tristan Titeux
Why do people always find reasons not to do something good like this rather than find the ways that it CAN be used.
Unfired bricks should be used where they are best used, and not where they are not, it's as simple as that.
Unfired bricks are sustainable because they don't use much energy to produce and can be easily reused or recycled at the end fo their life.
We need more such solutions for us as human's to have any hope of surviving.
One material should not dominate, we need to use as many different materials for different places and uses, that is another very important part of sustainability.
Thank you
Tristan Titeux