HOME  |  NEWS  |  BLOGS  |  MESSAGES  |  FEATURES  |  VIDEOS  |  WEBINARS  |  INDUSTRIES  |  FOCUS ON FUNDAMENTALS
  |  REGISTER  |  LOGIN  |  HELP
<<  <  Page 2/3  >  >>
j-allen
User Rank
Gold
Concrete fillers
j-allen   4/16/2013 2:02:26 PM
NO RATINGS
When I was in grad school the civil engineers would enter the annual concrete canoe contest where the teams would have to build a canoe entirely out of conrete and then race it against those of other teams.  Most broke up or sank before the finish line, but the builders did use unusual fillers to reduce the density.  One mix had a specific gravity of just 0.75, about equal to oak, and it had an amazing tensile strength, almost  two percent that of oak. 

Ann R. Thryft
User Rank
Blogger
Re: Corn, Wheat & Rice Trash Make Concrete Stronger
Ann R. Thryft   4/16/2013 11:56:04 AM
NO RATINGS
Thanks, Greg, for those examples. Mud brick goes back at least as far as ancient Mesopotamia in the Near East.

Ann R. Thryft
User Rank
Blogger
Re: Replenish the Soil?
Ann R. Thryft   4/16/2013 11:54:33 AM
NO RATINGS
You're absolutely right about "specific chemical requirements," which is what I said. But there's cellulosic and then there's cellulosic: they're by no means all the same. And the stuff we're writing about here is not leaf mold--which, BTW, can also vary widely in chemical content (for example, high tannin content in oak leaves).
Depending on its chemical composition, some cellulosic material adds nitrogen and other nutrients to the soil, some takes those out, and some doesn't do anything nutritionally, but does add bulk and loft, which is not always needed or wanted, BTW. The stuff being recycled here doesn't add much in the way of nutrients and/or can leach it out. It can also cause rot problems. This is a complex subject, which we touched on in the DuPont article. Check it out.

Elizabeth M
User Rank
Blogger
Re: Interesting use of these resources
Elizabeth M   4/16/2013 3:51:02 AM
NO RATINGS
Thanks for those links, Ann. I do remember reading your previous coverage, but always good to jog the memory, as one reads about so much. It's good to see this successful model being used and reused.

JGetaz
User Rank
Iron
Re: Replenish the Soil?
JGetaz   4/15/2013 3:59:56 PM
NO RATINGS
All gardeners know what they buy in a store - the synthetic, or maybe not, fertilizers I mentioned - have specific chemical requirements. Good gardeners also swear by leaf mold: cellulosic material partly consumed by mold that they turn under in the spring to give the soil more tilth. Sounds like what we're taking away from the soil this way.

Ann R. Thryft
User Rank
Blogger
Re: Interesting use of these resources
Ann R. Thryft   4/15/2013 3:44:14 PM
NO RATINGS
Elizabeth, the model of using waste plant material for making biofuel and bioplastics is already well underway, as we've covered in several posts in DN. One is the DuPont story about biofuel:
http://www.designnews.com/author.asp?section_id=1392&doc_id=257126
Another is using cane trash to make bioplastics:
http://www.designnews.com/document.asp?doc_id=237554

Ann R. Thryft
User Rank
Blogger
Re: Replenish the Soil?
Ann R. Thryft   4/15/2013 3:43:31 PM
NO RATINGS
Not all farmers want to recycle this stuff, for several different reasons (one being that cellulosic material doesn't make very good fertilizer, which has very specific chemical requirements, as any gardener knows). Some of them are covered in the story we did on DuPont using corn stover for making biofuel--we gave the link in this story, but here it is again http://www.designnews.com/author.asp?section_id=1392&doc_id=257126

Greg Stirling
User Rank
Platinum
Corn, Wheat & Rice Trash Make Concrete Stronger
Greg Stirling   4/15/2013 3:40:28 PM
NO RATINGS
Excellent use for recycled materials.  Concrete has been reinforced for eons to make it stronger or lighter.  From adding straw to mud bricks in thy neighbors hut, steel rebar in just about everything cast concrete, to adding limestone or pumice (lavarock) in the concrete domed cielings of ancient structures such as the Parthenon.  A building which has survived earthquakes and other factors for 1900+ years...

Elizabeth M
User Rank
Blogger
Re: Interesting use of these resources
Elizabeth M   4/15/2013 2:55:29 PM
NO RATINGS
When you put it that way, Ann, I definitely hope there will be other applications of this model! Surely something like this is already happening in the biofuel world?

JGetaz
User Rank
Iron
Replenish the Soil?
JGetaz   4/15/2013 2:05:33 PM
NO RATINGS
I would have thought it would be better to turn any such "waste" under to replenish the organic material in the soil. Since it is cellulosic, I would think this would also help keep the soil loose. This should make it a little less important to put synthetic fertilizers on the ground the next spring. 

<<  <  Page 2/3  >  >>


Partner Zone
Latest Analysis
Advertised as the "Most Powerful Tablet Under $100," the Kindle Fire HD 6 was too tempting for the team at iFixit to pass up. Join us to find out if inexpensive means cheap, irreparable, or just down right economical. It's teardown time!
The first photos made with a 3D-printed telescope are here and they're not as fuzzy as you might expect. A team from the University of Sheffield beat NASA to the goal. The photos of the Moon were made with a reflecting telescope that cost the research team 100 to make (about $161 US).
At Medical Design & Manufacturing Midwest, Joe Wascow told Design News how Optimal Design prototyped a machine that captures the wing-beat of a duck.
The increased adoption of wireless technology for mission-critical applications has revved up the global market for dynamic electronic general purpose (GP) test equipment. As the link between cloud networks and devices -- smartphones, tablets, and notebooks -- results in more complex devices under test, the demand for radio frequency test equipment is starting to intensify.
Much of the research on lithium-ion batteries is focused on how to make the batteries charge more quickly and last longer than they currently do, work that would significantly improve the experience of mobile device users, as well EV and hybrid car drivers. Researchers in Singapore have come up with what seems like the best solution so far -- a battery that can recharge itself in mere minutes and has a potential lifespan of 20 years.
More:Blogs|News
Design News Webinar Series
10/7/2014 8:00 a.m. California / 11:00 a.m. New York
9/25/2014 11:00 a.m. California / 2:00 p.m. New York
9/10/2014 11:00 a.m. California / 2:00 p.m. New York
7/23/2014 11:00 a.m. California / 2:00 p.m. New York
Quick Poll
The Continuing Education Center offers engineers an entirely new way to get the education they need to formulate next-generation solutions.
Oct 20 - 24, How to Design & Build an Embedded Web Server: An Embedded TCP/IP Tutorial
SEMESTERS: 1  |  2  |  3  |  4  |  5  |  6


Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.
Next Class: 10/28-10/30 11:00 AM
Sponsored by Stratasys
Next Class: 10/28-10/30 2:00 PM
Sponsored by Gates Corporation
Next Class: 11/11-11/13 2:00 PM
Sponsored by Littelfuse
Learn More   |   Login   |   Archived Classes
Twitter Feed
Design News Twitter Feed
Like Us on Facebook

Sponsored Content

Technology Marketplace

Copyright © 2014 UBM Canon, A UBM company, All rights reserved. Privacy Policy | Terms of Service