Tuesday, January 29, 2008

Floating Stones - Concrete Ships and Vessels

Picture_012Concrete ships are ships 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, the US military ordered the construction of small Picture_010 fleets of ocean-going concrete ships. 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.

A Brief History of Concrete Ships

lambot_dingy The first vessel made of concrete in Europe was a skiff built by Joseph-Louis Lambot at Carces, France on the Argens in 1849.  It was exhibited at the World Fair, Paris, in 1855. In 1859-60 in Holland, Fabriek von Cement-Iger Werken was producing concrete barges for canal traffic.

In the 1890's, an engineer in Italy named Carlo Gabellini built barges and small ships out of concrete. He used a ferro-concrete procedure to make hulls that were an elaborate lamination of rod netting, wire mesh, and troweled mortar. The most famous of his ships was the Liguria.

At Frankfort-am-Main in 1909, Germans produced a 220-ton freighter barge. In 1912 a concrete sailboat was launched at Dresden. And in England from 1912 to 1917, a fleet of canal barges, some with a capacity of 1400 tons, were in commercial service.

Numerous small concrete boats were built in the U.K in the 1910's. One of these ships, the Violette, was built in 1917 and is currently used as a boating clubhouse on the Medway River in England. This makes her the oldest concrete ship still afloat.

American construction in cement aggregate began in 1910 when a 525-ton scow was built in San Francisco along with some smaller barges for use in the Panama Canal. At Mobile in 1914, a 90'x62'x9' concrete barge as well as several 500-ton barges were built for local traffic.

In 1917, the United State finally entered World World I and steel became scarce while the demand for ships went up. The US government invited N.K. Fougner to head a study into the feasability of concrete ships.

Meanwhile, businessman W. Lesie Comyn took the initiative and formed the San Fransisco Ship Building Company at Oakland, California, to begin constructing concrete ships. He was convinced that a 5,000-ton concrete freighter could be operated at a profit and on 3 September 1917 he solicited contractual support from USSB to build "five reinforced concrete steamers" and was assured of nominal support on 22 October. On speculation, then, his firm began to build the Faith at Redwood City, California.

Lesie Comyn hired Alan Macdonald and Victor Poss to design the first American concrete ship. Alan Macdonald and Victor Poss designed the ship, a freighter, the first of her kind built in the United States, and, at the time, the largest concrete vessel with a sea-going capability in the world (300' x 40' @ 6125 tons displacement).

The Faith was launched March 18, 1918. She cost $750,000 to build. She was used to carry cargo for trade until 1921, when she was sold and scrapped as a breakwater in Cuba.

President Woodrow Wilson finally approved the Emergency Fleet program which oversaw the construction of 24 concrete ships for the war. However, only 12 were under construction and none of them had been completed by the time the war ended. The 12 ships were completed and sold to private companies who used them for light-trading, storage and scrap.

With the advent of World War II, steel once again was in short supply. In 1942, the US government contracted McCloskey & Company of Philadelphia, Pennsylvania to construct a new fleet of 24 concrete ships. Construction of the fleet started in July, 1923 in Tampa, Florida. Innovations in cement mixing and composition made these ships stronger than the previous fleet.

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, and as floating pontoons. Some were fitted with engines and used as mobile canteens and troop carriers.

atlantus1926_thumb Other companies were contracted to build barge ships. These too were large vessels, but they lacked engines to propell them. Instead, they were used for storage and towed around by other ships.

After the war, several of the ships were turned into a floating breakwater in Canada and ten more were sunk as a breakwater in Virginia.

Although the end of WWII marked the end of large-scale concrete ship building, to this day, smaller recreational boats are still being made from concrete.

Today

Surviving concrete ships are no longer in use as ships. Several live on in various forms, mostly as museums or breakwaters. For example, SS San Pasqual, a former oil tanker, lies off the coast of Cayo Las Brujas, Cuba, where it served as a hotel, then as a base for the divers and now it is abandoned. IMG_2679_500

The wreckage of SS Atlantus (commissioned in 1919, sunk in 1926), is visible off Cape May, New Jersey. The tanker SS Selma, 29°20′40″N, 94°47′10″W is located northwest of the fishing pier at Seawolf Park. The largest collection, though, is doubtless at Powell River, British Columbia, where a lumber mill uses ten ships as a breakwater.

Modern hobbyists also build ferroboats. The reason is that construction methods do not require special tools, and materials are comparatively cheap. A pioneer in this movement is Hartley Boats, which has been selling plans for concrete boats since 1938. Meanwhile, since the 1960s, the American Society of Civil Engineers has sponsored the National Concrete Canoe Competition.

In Europe, especially the Netherlands, concrete is still used to build some of the barges on which houseboats are built.

sources: The Journal of San Diego History, Wikipedia, The World Of Ferro-Cement Boats

1 comment:

Matt Capital said...

Violette is in fact sunk as a breakwater which the floating jetties are attached to.