Sunday, June 3, 2007

44. Environmental-proof/Waterproof/Airtight materials


Mark said...

Environmental-proof items, though a major human creation and 'success' of the 20th century, have come back to haunt us: anything environmental-proof is ecologically unsound if permanent. Exhibit A would be all that plastic floating in the oceanic gyres around the world since none of it ever degrades and since it only gets smaller and small with sunlight-induced dissociation into pieces. Then, it goes into food; clouds the clear water that plankton depend upon to feed within (from the sunlight, their food); and gets into fish; and gets into animals, birds, and humans and wreaks havoc on their hormonal systems. Hardly an elegant solution and more like a graveyard of human ingenuity.

Ideally, this category would be banned in some way, and all 'proof' conditions of any sort would be designed to be chemically reversible after long immersion or long sunlight degradation, particularly mass consumer items. Then the packaging would breakdown into something useful for life, instead of poisonous.

Mark said...

Perhaps moving back to recycled glass and stopping the production of plastics (that leach cancerous chemicals, that degrade without destroying itself--only into small pieces that kill oceanic life when swallowed over time, that are endocrine disrupting, and that bioaccumulate (toxic) petrochemicals).

There are many benefits to glass--

1. could be very durable for environmental-proof, waterproof, and airtight applications without leaching chemicals because glass is a slow moving fluid and thus less chemically reactive.

2. the human incentive is 'sharp' to clean up glass trash compared to plastic trash: if they are made that way, sharp edges of broken or discarded glass would be their own 'human ecological' incentive to clean it up instead of leave it lying around.

3. Since they fail to dissociate into smaller pieces and certainly fail to float, they would contribute to demoting the plastic gyres in the world's oceans since they would stop gathering in such areas. Instead, they would sink near shore or deep in the oceans. The former would be further incentive to clean it up and avoid letting that happen. By sinking instead of floating in mid ocean if dropped there, the latter would remove itself from interfering with the oceanic food chain.

4. If they are made that way, there are astounding recipes for glass that can handle incredible temperature and pressure gradients of thousands of degrees on either side without braking.

5. It's pretty infinitely recyclable, unlike plastics which are very pollutive to recycle.

Glass would be a fluid enough technology to be adaptable to many different applications, and its ingredients are very common in origin and thus its pollutions and environmental impacts of withdrawal can be made very low (or even zero, with solar melters, etc.) in its firing.

Plastic is a biotoxin and should be discarded, literally, as a material in this category.

There are other forms of materials that 'heal themselves' when damaged that could be utilized in this category as well.

Mark said...

[perhaps mix this idea with the 'pyramid' concrete mentioned in the building materials category.]

Better Bridges
Civil Engineers Test New Concrete for Stronger, More Durable Bridges

January 1, 2006 — A new kind of concrete called Ductal will allow bridges to hold more weight and last longer. Made of a mixture of sand, cement, water, and small steel fibers, it is 10 times more expensive than traditional materials but also stronger and virtually impermeable, helping bridges become more durable.

AMES, Iowa--Bridges take a beating, and it can really break the bank to repair them. Now, researchers are breaking bridges to learn how to build them better and save you money.

Justin Doornink spends his mornings underneath bridges. He's an engineering student and, as part of his homework, he's installing sensors to measure the impact of traffic on the bridge. He's trying to figure out how to strengthen the structures. One option is ultra-high-performance concrete, which is made from sand, cement, water and small steel fibers.

Brent Phares, a civil engineer and associate director at the Iowa State University Bridge Engineering Center in Ames, says, "It's much, much stronger. It's basically impermeable to water. What those two things mean is you can build a bridge that has a higher capacity and should last a longer period of time."

Brent did a small-scale test with the new concrete, pushing it to its breaking point. It held close to 595,000 pounds -- that's more than seven semi trucks. The material costs 10-times as much as traditional concrete, but you need less of it, and it lasts longer.

"You're never going to advance the state-of-the-art unless you do some research, try some things out, maybe take some risks and see what might ultimately save the taxpayers money," he says.

BACKGROUND: Engineers at Iowa State University have developed a new type of concrete that is much stronger than conventional concrete. It can withstand pressures up to 595,000 pounds -- more than the weight of seven semi trucks.

LOAD-BEARING BRIDGES: The researchers conducted a load-bearing capacity test using a 71-foot beam made out the new concrete. They applied increasing amounts of hydraulic pressure to the top of the beam to see how much it could withstand before breaking. It finally broke with a loud pop at 595,000 pounds. The ultra-high performance concrete is made from sand, cement, water and small steel fibers. Standard concrete uses coarser materials. The new concrete is specifically engineered to include finer materials and steel fibers, making it denser and stronger.

WHY THE BEAM BROKE: Isaac Newton said it best: for every action there is an equal and opposite reaction. As the hydraulic pressure on the beam increases, the beam responds by exerting an equal but opposite counter-force. But it doesn't do so uniformly: certain areas bear the brunt of the increasing pressure. This produces a strain on the beam, which eventually becomes too great, and the beam cracks.

DIFFERENT DEFORMATIONS: Different materials can withstand different amounts of deformation, a property known as elasticity. Most materials are elastic to some degree: when they are deformed or bent, they will bounce back to their original shape. But elastic materials all have their limits. Metal springs and rubber bands are very elastic. Plaster and glass are not; instead, they are brittle and snap even with a small deformation.

The American Society of Civil Engineers contributed to the information contained in the TV portion of this report.