Rethink Your Life!
Finance, health, lifestyle, environment, philosophy
The Work of Art and The Art of Work
Kiko Denzer on Art
[Cob] Fwd: cob shake test infodhowell at pickensprogressonline.com dhowell at pickensprogressonline.com
Sun May 20 10:34:27 PDT 2012
Begin forwarded message: > From: "dhowell at pickensprogressonline.com" > <dhowell at pickensprogressonline.com> > Date: May 20, 2012 1:33:32 PM EDT > To: Henry Raduazo <raduazo at cox.net> > Subject: Re: [Cob] cob shake test info > > Ed, > That is my primary concern also. I think it's common knowledge > that dirt leaches out iron. One thing I think is suspicious is that > bamboo has been tested to out perform steel rebar and it's a > fraction of the weight, yet there's never a mention of that. I > think bamboo dowels in cob walls (just laid across the wall and > cobbed around) would have the same function as steel rebar and > probably would keep the integrity of the wall. > It's a good time for proposing such a thing because there is > almost no new construction and the inspectors may be more willing > to take the time to learn about cob just to have something to do. I > just can't scare the daylights out of them by proposing an American > style cob house. Although they look cool and are sufficient, they > look like a nightmare to an inspector that looks at straight lines > and 90 degree angles in homes all day. > Damon > > On May 18, 2012, at 9:41 PM, Henry Raduazo wrote: > >> Damon: >> You are of course absolutely right, and cob is vastly superior to >> adobe. That does not make it easy to get approval. Usually to get >> approval there is such a huge safety margin that the net effect is >> to be almost prohibitive to natural building. >> People doing rammed earth structures used to put a little >> concrete in their mix just to make the inspectors feel happy. >> There was so little concrete in the mix and so much time between >> mixing and pouring the mix into the form that there was no >> strength imparted to the mix, but making inspectors feel good is >> important. >> I have done it both ways. I had one project where the inspector >> required me go go in and get special approval for a wall, and my >> other projects have been the "Don't ask don't tell" format. I >> have a huge respect for people like David Eisenberg who have >> devoted their lives to trying to get reasonable building codes >> that include natural building materials. >> I have been through the whole college routine too with strength >> of materials and concrete design... I understand how engineers >> think, and I wish I had an answer to this problem other than just >> doing it under the table. I think the adobe got approved just >> because the prior situation was intellectually embarrassing. >> Native people could not build and finance traditional structures >> in their homeland, but they were allowed to build and finance >> structures built with imported materials and technology foreign to >> their native culture and traditions. >> >> I wonder: if we took apart some of the 1000 year old Pueblo >> structures and randomly tested some of the 1000 year old bricks, >> do you suppose that these bricks would pass current Adobe code? I >> don't think current adobe code has anything to do with a realistic >> assessment of what is required for a structure to last 1000 years. >> The strength that a wall has the day it is manufactured and the >> strength it has 100 or 1000 years from now depends on the chemical >> and mechanical stability of the materials. That is why putting >> steel in cob or adobe bothers me. It is not chemically stable and >> it expands as it reacts with moisture or minerals in the wall >> material. Think about all the possible impurities in clay soil. >> >> I wish Good Luck to the Alpha Testers, >> >> Ed >> >> >> >> On May 17, 2012, at 2:52 PM, dhowell at pickensprogressonline.com wrote: >> >>> Ed, >>> Understood about quality control. I must point out concrete >>> mixes from scratch in a wheelbarrow can also have vastly >>> different strengths according to the amount of water used. Adobe >>> bricks? New Mexico Earthen Building Materials code states, "each >>> of the tests prescribed in this section shall be applied to >>> sample units selected at random at a ratio of five units per >>> twenty-five thousand bricks to be used or at the discretion of >>> the building official." Five out of 25,000 seems like a pretty >>> unrepresentative number for the whole. Quality control can be >>> done by performing tests at the foundation, sill height, and >>> lintel height of the walls. Did you know the adobe code allows a >>> psi of 250 and one out of five can have a psi less than that? >>> We're talking about the same material just a different building >>> procedure. Their code is a good guideline, but some things are >>> questionable, such as it requires concrete stucco which is an >>> accident waiting to happen according to the Devon Earth Building >>> Association. A healthy topic that must be discussed, don't you >>> think? >>> Damon >>> >>> On May 17, 2012, at 2:09 PM, Henry Raduazo wrote: >>> >>>> The problem might be one of quality control. When you are >>>> mixing something in a large batching machine (like a concrete >>>> mixer) you have large 3-5 yard batches which are perfectly >>>> uniform. When you have small crews making 1/27th of a yard >>>> batches on a tarp asserting quality control is a nightmare. >>>> Every crew can not make every batch the same let alone getting >>>> the 5 or 6 different crews to make uniform batches. >>>> I have been able to make uniform cob batches by mixing one ton >>>> batches on a concrete slab with a rototiller. That might satisfy >>>> a quality control person, but getting such anal persons to >>>> accept hundreds of batches made by half a dozen different crews >>>> might be expecting too much even if we had a code that described >>>> the material in a way to differentiate acceptable cob from >>>> unacceptable cob. >>>> >>>> Ed >>>> On May 17, 2012, at 11:29 AM, dhowell at pickensprogressonline.com >>>> wrote: >>>> >>>>> Thanks Ron, >>>>> As I mentioned; "but no paperwork which building officials >>>>> will accept." >>>>> >>>>> >>>>> On May 16, 2012, at 8:17 PM, Henry Raduazo wrote: >>>>> >>>>>>> but no paperwork which building officials will accept. >>>>> >>>> >>> >> >
Solar powered hosting (from our cob office building) provided by: DeaTech Research Inc. using Debian Linux based servers. We highly recommend, use, and provide support services for Debian Linux.
If you should have any problems with this page or website, please send email describing the problem(s) to: firstname.lastname@example.org
Last Modified: Monday, 21-May-2012 09:57:22 PDT
If you wish to be permanently blocked from ever being able to send email to this domain, send your SPAM messages to: email@example.com