A standard concrete is about to be launched at Bordeaux. It is a cargo boat of 900 tons, but several others over 1.000 tons will be built if the trials of this one prove satisfactory. This concrete vessel was built in less than three months, on an even keel, like the steel or wooden ships, and not like the 200-ton cargo boat recently launched at Christiania, with keel uppermost.
Source; Shipbuilding and Shipping Records, September 6, 1917, page 237.

300-TON FERRO-CONCRETE BARGE.

Widespread interest has been recently displayed by naval authorities and the shipbuilding industry in the possibilities of reinforced concrete for the building of ships, barges and other floating structures. This is due to a large extent to the fact that the world shortage of steel caused by the war has of necessity turned the eyes of naval architects to other directions in search of a material which shall displace steel in the construction of ships.

Many reports have reached this country of barges and other small craft which have been rapidly and cheaply built of ferro - concrete and which have been found eminently suited for the purposes they were designed to fulfil. But whilst these reports have given full details as to the over-all dimensions of the vessel, it’s displacement, rate of construction and cost, very little has been divulged as to the actual method of construction adopted, nor have the dimensions of the various parts of the structure been given. We are able this week to supplement the usual description of this type of vessel by a detailed drawing of a 300-ton coal barge which has recently been built on the “ Hennebique “ system of ferro concrete construction for the French National Marine, from which the details of the construction of the vessel and the dimension of the various parts of the structure can be seen.

The chief dimensions are as follows:-

Length, overall                               94 ft. 0 in. (approx).
Length between perpendiculars  91 ft. 10 in.
Breadth                                            19 ft. 6 in.
Depth                                               11 ft. 4 in.

The barge draws 9 ft. 6 in. of water when loaded with 200 tons of coal, and 11 ft. 6 in. when carrying a load of 200 tons.

The general details of construction are given below, the drawing showing the half-profile and half -longitudinal section of the hull together with half-plans of the deck and hold of the vessel. It will he noticed that the vessel has a double bottom and is divided into six separate compartments by means of five watertight bulkheads, access to each part of the hold being obtained by means of iron ladders. The hull is constructed upon what may be considered as a combination of the transverse and longitudinal system of framing, there being a series of transverse frames spaced 3 ft. 33 in. apart and passing right round the hull save for the opening at the deck which is 12 ft. 10 in. wide in the parallel or midship portion. These transverse ribs which are of concrete reinforced with steel rods to enable them to withstand bending stresses are rectangular in section, 31/8 in. wide by 13 3/4 in. deep. The longitudinal frames are also spaced 3 ft. 3 3/8 in. apart and run the whole length of the vessel, the sides as well as the bottom being stiffened in this way. These longitudinal frames, reinforced similarly to the transverse frames are also 3 1/8 in. wide and 13 3/4 in. deep, and thus the skin of the vessel is divided up into a series of squares which are covered with concrete slabs, the whole being cast so as to form a continuous structure. The waining around the openings in the deck is also made 3 1/8 in. wide, but the depth is increased by two inches to 15 3/4 in. The customary accommodation is provided for the crew and the accessories of the barge include pumps, winch, davit, bollards and hawseholes for ropes or cables.
The arrangement of transverse and longitudinal ribs coupled with a well-designed system of reinforcement enables the outer skin of the hull to be cast of the minimum thickness. This desirable result is also due in no small measure to the monolithic character of the structure throughout. As a consequence of the relatively thin hull of the vessel, the weight of the barge is found to be only a small percentage more than it would have been if steel had been adopted, while the initial cost is considerably lower. Moreover, the avoidance of future annual charges for upkeep will result in a greatly increased ultimate economy.
Two views are given on page 420, the first showing the barge under construction, and the second showing the completed barge after it has been launched, the photograph having been taken when the vessel was resting on its bottom in very shallow water.
We are indebted to Mouchel & Partners, Ltd., 88, Victoria Street, London, S.W. 1, who are contractors in this country for the well-known Hennebique system of reinforced concrete construction, for the illustrations and particulars from which this article has been prepared, and it should be pointed out that the dimensions given above have all been obtained from the dimensions given in French units to which the vessel was constructed.
Source; Shipbuilding and Shipping Record, November 1 1917, page 420 – 421.

 FRENCH CONCRETE SHIPS.
In our issue of March 7 we published a set of photographs illustrating the building of some reinforced concrete vessels for the French Government, the vessels being constructed to act as armed river transports. The first photographs were taken during the earlier stages of construction and give a good idea of the formation of the hull. We publish on pages 313-315 a second series of photographs illustrating the building of the same vessels, but showing them in a later stage of construction, and giving an idea of the finishing stages of the job, and also the method of launching.The photographs were published by the French Ministry of War for the Press Bureau of Paris, and issued in this country by the Topical Press Agency.
Source: Shipbuilding and Shipping Record, March 21, 1918.

COMAFRAN 1 (m/v)
Build 1918
360 grt, 186 nrt.
Dim: 45,57 x 7,54 x 3,76 m.
Engine: 2 Petrol Panhard-Levasseur, France, twin screw.
Owners:
1918. Fontaine & Co., Rouen, France.
1928: T. H. Skogland & Son A/S, Haugesund, Norway.

      
Launch of m/v COMAFRAN 1

 From buildingsite at the banks of river Seine.

COMAFRAN II (m.v.)
Build 1919.
404 grt, 206 nrt, 1.000 dwt
Dim: 46,78 x 7,33 x 3,76 m.
Engine: 2 Oil, Atlas-Polar.
Owner:
1918. Fontaine & Co., Rouen, France
192?: Compagnie Franco-Anglais

Last updated 2005.09.05.