Concrete Is Remixed With Environment in Mind

Soaring above the Mississippi River just east of downtown Minneapolis is one remarkable concrete job.

There on Interstate 35W, the St. Anthony Falls Bridge carries 10 lanes of traffic on box girders borne by massive arching piers, which are supported, in turn, by footings and deep pilings.

The bridge, built to replace one that collapsed in 2007, killing 13 people, is constructed almost entirely of concrete embedded with steel reinforcing bars, or rebar. But it is hardly a monolithic structure: the components are made from different concrete mixes, the recipes tweaked, as a chef would, for specific strength and durability requirements and to reduce the impact on the environment. One mix, incorporated in wavy sculptures at both ends of the bridge, is designed to stay gleaming white by scrubbing stain-causing pollutants from the air.

The project, built for more than $230 million and finished in September, three months ahead of schedule, “might have been the most demanding concrete job in the United States in 2008,” said Richard D. Stehly, principal of American Engineering Testing, a Minneapolis firm that was involved in the project. It is a prime example of major changes in concrete production and use — changes that make use of basic research and are grounded, in part, in the need to reduce concrete’s carbon footprint.

Concrete may seem an unlikely material for scientific advances. At its most basic, a block of concrete is something like a fruitcake, but even more leaden and often just as unloved. The fruit in the mix is coarse aggregate, usually crushed rock. Fine aggregate, usually sand, is a major component as well. Add water and something to help bind it all together — eggs in a fruitcake, Portland cement in concrete — mix well, pour into a form and let sit for decades...

Actually, by using slag and fly ash, they probably saved a bundle over the cost of portland.

If so, I think it’s a good way to help the environment.

I’m one who doesn’t care if glowbull warming is fact or fiction, man made or not. I prefer to reduce pollution, in all it’s forms, if at all possible, as long as it’s not at the cost of human or domestic, farm or animal life, or human quality of life.

I prefer clean over dirty, beauty over ugly, and health over illness. I want our children and grand children, etc, to know the beauty of the Country I love so much, and yes, even the foreign Countries I have visited. So, I choose to help, rather than hurt, the environment whenever and wherever I can. As long as my qualifications are met, I’ll continue to do so. It’s really a Conservative thing, ya’ know. LOL

We could go green, very cheaply, if the enviro-nazis would wake up and smell the Roses.

Use natural gas, instead of gasoline and diesel in our cars and trucks. Use nuclear energy, instead of coal, to generate our electrical needs. Use methane for low energy needs, it’s free, and it’s everywhere.

Give industry an incentive to go green, and they will, penalize them and tax them to death, and they won’t. They’ll just go overseas.

You want Cap and Trade? Fine, make it a free market program without Gov’t interference or penalizing mandates. Don’t tax the money that is generated of the C&T exchange, you’ll see a major reduction, muy pronto!

If we switched to natural gas (CNG or LNG) as a “bridge”, we would be able to take the time necessary to develop a renewable, clean, cost efficient, fuel. And, we’d create about one million net jobs...in America.

America invented the term “recycle” in the context of re-use of materials, yet we lag almost the entire western world. Why? The cost to recycle is enormous, and the cost of recycled products, in many cases exceeds the virgin product it replaces. A simple tax incentive for the recycling industry would change that.

These are but a few ideas that could make a big difference. But, do you think the F***heads in the position to do something care? Hell no. Why? because it’s NOT about the environment to them, it’s about the transference of money, sovereignty, and ultimately, power to control the world. (sounds scary, doesn’t it?)

I prefer clean over dirty, beauty over ugly, and health over illness. I want our children and grand children, etc, to know the beauty of the Country I love so much...

I have yet to meet ONE person who prefers dirty air over clean air or an ugly environment over a beautiful one...

I can't find anyone - not one conservative - who likes filthy polluted lakes rather than clean sparkling ones.

Have you bought into the liberal straw man argument? The argument that says liberals want to breath clean air, but conservatives want to breath dirty air?

No, and I didn’t mean to imply that I did, either. Actually, what was in my head was the charges by the left that Conservatives are Earth rapers, and don’t care about the environment.

I know that to be false. I highly doubt, for instance, that you would ever see a Conservative empty his ashtray in a parking lot, or throw his fast bag of trash out the window.

I use these examples because I’ve witnessed people with either anti-Bush stickers, or support stickers for DUmmies on their cars doing these things.

I highly doubt, for instance, that you would ever see a Conservative empty his ashtray in a parking lot, or throw his fast bag of trash out the window.

Any ONE individual conservative or liberal might do almost anything. But if you look at large gatherings of liberals, they're pigs. Every bit of garbage in the world in thrown on the ground. Even if there are trash receptacles within two feet.

Also for all their big talk - liberals don't tip well - guess all that "concern for the working man" is an excuse to hit the middle class - not real concern for workers. And it goes on and on. They talk one way and act the opposite.

They have paid professional liars who work to break up our right to assemble - to communicate with each other. It's a tactic Hitler used. Check out a conservative "tea party" and you'll find that trash cans are full - and the street's not...

Look for the larger patterns - not just random people in cars - you might have a subconscious filtering system going that would skew your results.

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