Any ABS,ISO etc. Standard for Concrete Hull

Is there any standard for concrete hull scantling ?

Thank you,
Mustafa Umut Sarac
Istanbul

 

There WAS a published booklet that based scantlings on, IIRC, steel ship scantlings. It basically provided some formula to derive one knowing the other. You needed actual data from slump tests of the intended cement for use with the formulas. I believe this was created by one of the American agencies, but it has been a while since I saw it.

The one book I've downloaded and have on this iPad might reference this conversion scheme, not sure if it does (an appendix does give what were then Lloyd's rules, but these don't seem to present a way to determine scantlings). It's "An Introduction to Design For Ferrocement Vessels", Ottowa/Hull 1972.

There was another book about building FC fishing boats that may have referenced those conversion formula but I cannot be sure if I'm remembering that correctly. As I recall, this book had extensive drawings of the shop set up to build such a boat, the requirements for same, which may help you to find the one I'm thinking of.

Chapter 10 of this: http://www.fao.org/docrep/003/v9468e/v9468e00.htm#Contents

... gives some scantling rules "Whilst working in India, the American Bureau of Shipping was approached with a view to obtaining classification of future vessels built in India." The guidelines, from 1986, cover 10 to 20 meter boats. They may have been based on the conversion formula which may be older, I just can't remember, sorry. Still, they may give you somewhere to search.

 

This link is a translation of a Russian study of Ferrocement construction, published in 1968:

http://www.dtic.mil/dtic/tr/fulltext/u2/680042.pdf

This is an article on large concrete ships, including the handful built during both world wars as emergency construction:

http://www.concreteconstruction.net/images/Going to Sea in Concrete_tcm45-356660.pdf

The article has references to other works on concrete at the end.

This is a study by the Ship Structure Committee on experience with concrete construction:

http://www.shipstructure.org/pdf/321.pdf

There are other articles and papers, but these seem not to be available on line.

As far as I can tell, you can use the modern ABS rules to give you some idea of the loads which a concrete vessel can be designed to withstand, but these rules are developed solely for steel construction as far as scantling design is concerned.

 

There were in times past but as far as I know none of the class societies do now.

You don't say what sized boat or for what purpose. Barges have been made successfully out of concrete with pre-tensioned steel reinforcement. Many small boats are ferro-cement.

You can find a good guide to building ferro cement fishing boats on the FAO website here:

http://www.fao.org/docrep/003/v9468e/v9468e00.HTM

Chapter 10 of that document refers to ABS classifying ferro cement construction for the FAO
http://www.fao.org/docrep/003/v9468...ION AND CLASSIFICATION OF FERROCEMENT VESSELS

 

Good morning Mike ,

I am thinking less than 6 meters sail boats and more than 6 meters sail boats.

Thank you for reminding.

 

Found it!

https://books.google.com/books?id=b...UO#v=onepage&q=ferrocement scantlings&f=false

The link takes you to the page in a book which relates steel construction scantlings to ferrocement. As I recalled, the modulus of rupture is obtained from testing samples (or at least assumed from test data, I suppose)

These rules are probably going to yield a hull for hard use, which may be too heavy for your interests. Hartley's Ferrocement Boats book, http://www.hartley-boats.com/books.html , may be closer to the mark.

 

hmmmm, looking back on the posts in the thread "Found it!" may have been an overreaction since it turns out I and others keep finding the same thing.

 

http://www.nmsa.gov.pg/PDF_files/uslc-section_5_sub-section_J.pdf

Not sure if anyone has bothered for a decade or three.... although I have seen a couple of pontoons.

Jeff.

 

A couple of months ago I came very close to purchase of a 36' ferro-cement trawler built in Ottowa in the 1970s - it had been cruised through the Abacos annually for many years. Ultimately, I chickened out due to rotting in the glass/plywood superstructure, engine issues, and insurability issues.