concretesubmarine.com/ FORUM

http://www.kgrawood.com/bb.htm

http://www.hartley-boats.com/ferro.html

http://vimeo.com/50990903

The above material was prestented as solution to floating concrete shells - my answer was:

The rebar i see in those videos is supposed (and designed) to be the “fiber component” of a 20cm strong structural concrete wall and have a concrete cover of at least 3cm (according to european concrete engineering norms) to “avoid its rusting” – so to make it part of a 2cm wall and leave it under merely 1mm concrete cover and complicate the proper embedding of the steel by “littering the place” with chicken wire that hinders as proper void free embedding of the fiber component into the cement matrik additionaly, is a “clumpsy and unwise use of the fiber component” at best. In fact it is “utmost surprising” that there are shells that where built with that kind of method that do NOT rust and fall apart in a decade. That talks good of the “craftiness” of their builders in the sense that they got relative good embedding in spite of the chicken wire hindering them. If i would have the task to figure out a method to produce “short lasting shells” i would really choose something like that…a good shell will last 200 years for sure and probably 2000 years (as the Panteon) without showing minor signs of decay – so the fact that a few “ferrocement shells” last a couple of decades does not say a lot either. When talking about seasteading we need foundations that last centuries or millenia in marine ambient – i doubt that methods like shown in the videos and pictures are up to that task.

I would suggest to look into the following:

1) do not use steel rebar if you can not assure a proper embedding depth of 3cm.
2) forget the clumpsy chicken wire.
3) find a better method to hold the wet matrix material in place while curing than chicken wire.
4) explore non rusting fiber components where the required cover of 3cm can not be achived.
5) keep steel reinforcements out of the “spashzone” where corrosion is expected to be worst.

Basicly ferrocement is only on the table because it was the “first idea” of Joseph Monier to introduce some kind of fiber into a cement matrix and get a composite material out of it.
http://en.wikipedia.org/wiki/Joseph_Monier
Like always the “first idea” almost never is the “best idea” the better ideas come if you give it a second third, and fifth tought – that include feasible solutions to the above list of issues. Just forget “ferrocement” and think about smarter fiber components and smarter fillers and smarter aplication methods, do a series of tests find the better way. With space age fiber components and understanding of shell structures at hand we can really do a better job than the “ferrocement” invention of Monier…