The Art of Precast – Concrete Ships
The oldest photographic evidence of a concrete ship dates from 1848 and was about Joseph Louis Lambot's dingy. The boat was featured in the 1855 World's Fair in France. 1st patents were applied and called "Ferciment" – or as the Italians say: "ferrocemento".
Concrete is impermeable thanks to osmosis
Other swimming artifacts like swimming pontoons, hotels, working platforms etc. followed quickly, due to the ease of forming and excellent impermeability of concrete. In fact, concrete gets its "impermeability" mainly through osmosis and this is rather advantageous for concrete; adversely to glass-fiber-reinforcement.
Concrete Ships followed Steel Shortage
A first significant peek in concrete-ship construction was reached during the 1st world war 1914-1918.
Shortage in steel and available workforce imposed a general re-thinking of things, taking in account existing resources. The use of concrete reduced steel consumption by up to 70% and increased the output of shipyards per day. Building contractors, such as Wayss & Freitag or DYWIDAG (Dyckerhoff & Widmann) would have built over 200 ships.
R&D after WW1
The period from 1919 – 1938 can be considered as the prototyping period for concrete ships. Several (big!) ships had been built or transformed from warships to merchant ships. Many of those ships were started during WW1 and finished after. E. g. SS Sapona. 1926
Concrete ships sink as fast as wooden ones
The construction methods included the use of light aerated concrete with 2 coats in- and outside. This is very similar to today's double-body-technique, considered as "unsinkable". The country to have built the most vessels in ferro-cement is the UK. An estimated 9 million tons were built in the period Sept 1943 to May 1944 alone.
Even an british submarine is known to be built out of concrete:
And today?
Obviously, even concrete ships reach eventually their economic or technical end. However, the 1943 built MS Treue is used today, 73 years later, in Bremen Germany as a restaurant.
Up to now, around 11'000 Hartley concrete boats have been built. Over half of them are still operating.
Concrete Canoeing Event
Since 1986 every year Deutsche Betonkanu Regatta with over 100 crews from all over Europe. Usually those boats are built by students during their bachelor's degree.
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7yI remember 1980-90 we had a sailing boat in Finland made of concrete, the brand name was "Trollö" (the translation of the name is familiar for some of us..) the designer was a Finnish guy Juha Heikola and most of the boats were sold to self-builders who only both the concrete hull and built the superstructure of wood or glass fiber.
Director at RSTEEL® ( R-GROUP BALTIC OÜ).
7yHienoja paatteja. En tiennytkään, että jopa sukellusvene on tehty betonista. Sen kyllä tiesin, että kuulemma tietyn mittainen alus, on kevein betonista tehtynä. Siis ettei teräsksestä saa samankokoista yhtä kevyenä - liekkö sitten totta?
Very interesting post, I had never known this application of concrete before!