Vincent E. Pacheco Blog: Did they make ships out of concrete in WWII?

Tuesday, February 14, 2017

Did they make ships out of concrete in WWII?

Yes.

This was not new technology by WWII. Experiments had been ongoing in Europe for decades and the US had built some in WWI.

Concrete ships are built of steel and ferrocement (reinforced concrete) instead of more traditional materials, such as steel or wood. The advantage of ferrocement construction is that materials are cheap and readily available, while the disadvantages are that construction labor costs are high, as are operating costs. (Ferrocement ships require thick hulls, which means extra mass to push and less space for cargo.) During the late 19th century, there were concrete river barges in Europe, and during both World War I and World War II, steel shortages led the US military to order the construction of small fleets of ocean-going concrete ships, the largest of which was the SS Selma.[1] Few concrete ships were completed in time to see wartime service during World War I, but during 1944 and 1945, concrete ships and barges were used to support U.S. and British invasions in Europe and the Pacific. Since the late 1930s, there have also been ferrocement pleasure boats.

In Europe, ferro cement barges (FCBs) played a crucial role in World War II operations, particularly in the D-Day Normandy landings, where they were used as part of the Mulberry harbour defenses, for fuel and munitions transportation, as blockships, and as floating pontoons. Some were fitted with engines and used as mobile canteens and troop carriers. Some of these vessels survive as abandoned wrecks in the Thames Estuary; two remain in civil use as moorings at Westminster. One notable wartime FCB, previously beached at Canvey Island, was destroyed by vandals on May 22, 2003.

In 1944 a concrete firm in California proposed a submarine shaped freighter which they claimed could achieve speeds of 75 knots. The war ended any more research into the project. In retrospect many believe the claims were greatly overstated.

Concrete barges also served in the Pacific during 1944 and 1945. From the Charleroi, Pennsylvania, Mail, February 5, 1945:

Largest unit of the Army's fleet is a BRL, (Barge, Refrigerated, Large) which is going to the South Pacific to serve fresh frozen foods — even ice cream — to troops weary of dry rations. The vessel can keep 64 carloads of frozen meats and 500 tons of fresh produce indefinitely at 12°F. Equipment on board includes an ice machine of five-ton daily capacity and a freezer that turns out more than a gallon of ice cream a minute. Three of the floating warehouses, designed for tropical warfare, have been built of concrete at National City, Calif., and cost $1,120,000 each. In the crew of the 265-ft. barges are 23 Army men.

Concrete ship - Wikipedia

$1,120,000 adjusted for inflation is $15,000,000 in 2016 dollars.