Concrete Shipbuilding in San Diego, 1918-1920
Headlines in the June 12 and 14, 1920 issues of the San Diego Sun and, later, on June 29, proclaimed the launching of two new ships built in San Diego:
LAUNCHING OF THE "CUYAMACHA" SEEN BY THOUSANDS
The "Cuyamacha" -- San Diego's own ship -- rode the tide of San Diego Bay
LAUNCHING IS SUCCESS
Amidst cheers from crowds on shore and afloat, the "San Pasqual",
sister ship of the "Cuyamacha", slid down the ways at Thirty-Second Street shipyard...
With those announcements, two ocean-going tankers were readied for service in the American merchant marine. Planned for war-time use, they would be the first to carry San Diego's name into the blue water trade.
Not widely known today, the prospect of building two deep-draft vessels was at that time a welcome addition to the local economy. They were meant to become part of the "bridge of ships" that would carry supplies and soldiers to Europe.1 A nation-wide effort was made in 1917-18 to put a merchant fleet at sea and to replenish the tonnage lost following German submarine sinkings in the North Atlantic. One end-product of that vigorous effort in shipbuilding was a 40-ship "stone fleet" whose hulls were made from sand, gravel, and cement that enmeshed a fabric woven of steel rods. That shipbuilding activity was essentially an experiment intended to test whether concrete and steel mesh was a reasonable alternative for steel conservation.
The choice was sound. A few small coastal freighters made of reinforced concrete were busy in European waters by the summer of 1917, their engineering capabilities equal to conditions met at sea. Those ships suggested an option U. S. planners could explore. Few North American resources were as abundant and exploitable as cement and aggregate, shipyard labor was available, building sites were at hand...and new ships were desperately needed.
Succinct accounts of the vessels were given in the newspapers at the times of their launchings.2 Haviland gave the best coverage of the design, construction, and disposition of the class on a national scope3, whereas specific features of the design were delineated in meticulous detail in Webster's Shipbuilding Cyclopedia4 Wason, Wig, and Hollister commented on significant steps in construction ; an excellent description of the Pacific Marine Construction Yard was written by Bush. H.C. Turner's reports gave evaluations of ship behavior, production methods, and costs.6 Photographic coverage of the ship construction and building site is held in San Diego History Center archives and is annotated in Appendix A. Particulars reflecting current literature review are to be found in Williams' recent article7.
The first vessel made of concrete in Europe was a skiff built by Maurice Lambot at Carces, France on the Argens in 1849. It was exhibited at the World Fair, Paris, in 1855.8 In 1859-60 in Holland, Fabriek von Cement-Iger Werken was producing concrete barges for canal traffic. These were meant for lading, the largest being 648' x 48' and capable of 55 tons carriage. Cellular compartmentation by longitudinal and transverse bulkheads six feet apart lent tremendous strength to the hulls, which were virtually unsinkable. About the same time a Dutch enterprise used "ferro-cement" in a recreational motorboat. In that process, a steel framework of rods covered with a mortar yielded a hull 1/2" thick. Hence, the elements for reinforced concrete ship construction were in place 150 years ago. Not yet in existence, however, was the technology for high-volume, high-quality concrete shipbuilding. Nor were there design manuals or shipyard know-how to guide designers, engineers, and managers. Neither businessmen nor shipowners had enough practical insight to decide whether a concrete ship could sail at a profit.9
In 1897, in Rome, Carlos Gabellini manufactured a series of scows, barges, rowboats, and pontoons. He used a ferro-concrete procedure to make hulls that were an elaborate lamination of rod netting, wire mesh, and troweled mortar. 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.
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.10
The first ocean-going steamer built of reinforced concrete appeared on 2 August 1917 when the Norwegian Namsenfjord was launched by Fougners Stall-Benton Skibsbygnings Companie at Christiana. An 84-foot motorship designed by Nicolay K. Fougner, her plans had been approved by the State Director of Shipbuilding only in March. She sailed on her first commercial voyage on 31 August across the North Sea toward Harwich. Following classification by Lloyds in September, a half-dozen coasters were built, and all were found entirely satisfactory for short sea carriage by performance. Conventional standards for stability, watertight integrity, and propulsion efficiency were met and exceeded in these small freighters.11
1849 Concrete skiff made in France.
(In World War II, concrete barges and small naval oil tankers were built in National City. The record does not indicate whether the technology of the earlier building program was utilized.)
One consequence of war would be a serious shortage of seasoned lumber, said W. Leslie Comyn, a San Francisco businessman. In making his views known to the United States Shipping Board (USSB), he likewise pointed out the lack of steel-making plants and shipyards on the West Coast. His solution: build ships of concrete. Without pause and toward that end, he founded the San Francisco Shipbuilding Company at Oakland, California.12 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.
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).13
She was launched on 18 March 1918, six weeks after the pouring of the concrete was started...(had) machinery aft, 3427 gross tons and 2071 tons net, with triple expansion engines (sic) of 1700 I.H.P. giving her a speed of about ten knots.13
"Faith" left San Francisco 22 May on her first voyage commercial with a cargo of rock salt and copper ore assigned to Seattle. She traded in the eastern Pacific, Caribbean, and North Atlantic until December 1921.15
Near the end of November 1917, Secretary of Commerce William C. Redfield personally encouraged USSB chairman Edward Nash Hurley to become more active in concrete shipbuilding planning. Redfield had been impressed by arguments put forward by Rudolph J. Wig, a Bureau of Standards engineer, who had been recently observing activities in Europe and was convinced there were "...advantages of concrete for shipbuilding...(too) important to ignore." By mid-December Hurley formed the Department of Concrete Ship Construction, to be headed by Wig.16
America's entrance into World War I electrified shipbuilding planning, and at the same time highlighted the woeful conditions that existed in the merchant marine, its ships, and their crews. Neglect by Congress, disinterest of the public, and short-sightedness of the business community had placed the shipping of the country in a state of impoverishment. Fortunately, a practical step had been taken in 1916 when, in the first of several steps, Congress set about to rejuvenate foreign shipping trade. On 7 September an alerted Senate and House had empowered the United States Shipping Board to encourage and develop a vigorous merchant marine...and not too soon.17. With war in the offing, the USSB had to oversee the construction and operation of a greatly enlarged U.S. merchant fleet. The task was correctly seen as formidable -- how to move American armies to the Continent as well as provide logistic needs for a coalition?
First-order estimates called for 3 million men or, possibly twice as many more to fight on European soil. The logistical load would be 6 tons per man -- or more. Shipping capacity was estimated at first to be 18 million deadweight tons -- and might even be higher. All that, when there would only be 3 million tons available by June 1918. Clearly, what had to be done was to be on a massive scale.18 USSB managers stated their objective to be 1,200 ships of 6 million tons in 1918 and 9 million tons during 1919 by negotiation, contract, and angary.19
Submarine warfare was doing away with ships faster than they could be replaced, and Allied planners felt 9 million tons would be needed for each year of war for replacements. The Emergency Fleet Corporation (EFC) came into force on 6 April 1917 with its purview to be all USSB wood and steel shipbuilding programs.20 As it happened, the wooden shipbuilding phase, at stop-gap, failed to produce enough ships solely because of seasoned-wood stock shortages.
Concrete augmentation was proposed as an option for steel conservation.
...the hull of a concrete ship required (for reinforcing) only about as much steel per ton of deadweight as is required for the hull of a steel ship.21
Shortage of steel was a major factor in persuading the government to build concrete ships. A great attraction of concrete ships was that they could be built cheaply. An unlimited supply of sand, the primary building material, was available, and skilled shipyard labor was not needed in large numbers. There was a nagging doubt, however, about the seaworthiness of these untested hulls.22
By the end of October 1917, Nicolay Fougher, "Namsenfjord" designer, and his brother, Hermann, also its builder, had come from Norway by invitation to meet with USSB officials. Creation of a concrete ship construction group soon followed.23
The Concrete Ship Section was formed on 1 January 1918. An initial design effort centered on determining the features for a mix of 3,000 to 5,000-ton dry cargo and petroleum product carriers. In the meantime, the Senate Committee on Commerce voted for EFC to begin a study of the "feasibility of concrete over-sea ship construction" on 29 January. Support was bipartisan and included California's progressive Republican Hiram W. Johnson. In fact, there was already a private concrete ship project underway in San Francisco Bay.
The newly-formed Concrete Ship Section wasted no time in starting a full-scale investigation with detailed theoretical studies and extensive testing. Data soon provided the frame-work for an exhaustive report by Wig to the USSB chairman. Investigators concluded:
...that the concrete ship would be durable for at least several years; that the cost would be between $100 and $125 per ton deadweight for the completed ship; that the construction of concrete ships would not interfere with the existing program for building of steel and wooden ships; and that, if operations were started at once, 560,000 deadweight tons of concrete ships could be completed by the end of 1918.24
On 12 April 1918, President Wilson authorized a shipbuilding effort along the lines recommended by Hurley, who, after receiving the Wig report, sought action for obtaining a mix of concrete ships and an assortment of barge designs under a $500,000,000 program. As opposed to that, counter-arguments decried that:
a. concrete vessels had not been proven by service,
b. hull weight was greater than either wooden or steel ships,
c. salt water would hasten deterioration,
d. concrete was not up to withstanding seaway stress,
e. engine vibration would destroy concrete hulls,
f. unskilled labor could not be used for concrete work,
g. torpedo explosions would pulverize concrete hulls, and
h. industry could not furnish enough engines, boilers, and deck furniture for wooden, steel, and concrete ships.25
By 8 May, EFC had expanded its program for new yards and ship construction such that 38 ships were on order, contracts signed. Both San Francisco and San Diego benefited immediately. Eight cargo carriers were to be built in San Diego; however, no work was scheduled there for any of twenty-one 500-ton barges.
EFC let its San Diego contract on 3 June 1918 to Philadelphia's Scofield Engineering Company for eight 7,500-ton concrete cargo ships to be built in the shipyard founded for that purpose. Soon afterward the language of the contract was changed to read 'tankers', but in any case the event was noteworthy in the industrial life of the city. While the design task was beyond the reach of the engineering community, construction and outfitting were not. The city had never seen an engineering project of such magnitude.26
The San Diego Common Council ordered the leasing of tidelands at the foot of 32nd Street "...for the purpose of shipbuilding." An allocation was made for 22.0 acres of land and 77.2 acres of water surface. This parcel was formally deeded on 3 September 1919 to USSB in accordance with Ordinance 7433 dated 12 July 1918.27
Acceptance of the contract in June was a signal to begin building the yard as well as a channel leading to the deeper waters of San Diego Bay. Dredge tailings from the proposed launch and outfitting basin sites were laid out on tidelands so that shipyard buildings could be erected. Plans called for machine and foundry shops, bending and shearing sheds, cement and chandlery storage, mold loft, restaurant, and offices. The Pacific Marine Construction Yard managed by E. M. Scofield quickly took shape. Locally, it was known as "Scofield's Concrete Company".28
The first concrete was poured 28 May 1919. Within days, in order to accommodate radical design changes, work was stopped for five months. So as not to lose too much time, an unorthodox decision was made to outfit the ships while they were still on their ways before launch. This was contrary to conventional practice and a 'first' in the national program.29
The war with Germany demonstrated a deplorable state of U.S. merchant marine affairs. This situation had come about after fifty years of Congressional neglect, public disinterest, and lack of business acumen. A galvanic response to this realization led to the creation of the Emergency Fleet Corporation by the United States Shipping Board in 1917. At that time there were 51 yards in the country; those yards had 234 ways open. At war's end 186 yards were operating, and ships spewed off 898 ways. Under EFC programs, eight 7,500-ton tankers were launched:
|1920||Latham, Salem||Fred T. Ley Company, Mobile|
|Palo Alto||San Francisco Shipbuilding Company, Oakland|
|Cuyamaca, San Pasqual||Pacific Marine Construction Company, San Diego|
|1921||Peralta||San Francisco Shipbuilding Company, Oakland|
|1921||Moffitt, Dinsmore||A. Bentley Company, Jacksonville|
The basic configuration of any ship is the same regardless of the building material. The basic design is that of a box, pointed at one end and rounded at the other, and a cover is placed on the top with hatches and ladders at intervals to provide access. Typical World War I vessels contained oil-fired boilers that supplied steam to a reciprocating engine.
The tankers discussed here can be likened to a 50-story watertight building lying on its side in deep water. Engineers compare a ship to a bridge; both are built as box girders. Because of its structure, a ship floats on its side and, as waves pass down along its length, it will flex at the ends. This gives the naval architect a complex engineering problem to solve, because a ship not only "sags" (bends downward in the middle) but "hogs" (arcs upward from the same position) as waves pass from forward to aft. Then, too, the vessel will roll, pitch, or yaw as it rotates about its three axes, as well as bodily -- with no rotational movement -- "heave" (go straight upward), "surge" (move straight backward or forward), and "sway" (move sideways).
Shipbuilders achieve the shape and strength of a hull by assembling a multitude of curved and flat pieces of wooden blocks or steel plates. With a concrete hull there is only one piece, and its curved surfaces are attained by pouring a plastic mix into a hollow mold, which is a series of forms made on the site. The hull assumes its designed shape as the mix solidifies.
Unlike an office building, the ship hull must be erected on a sloping surface so that gravity can be used to launch it. For that reason, temporary underpinning keeps the hull vertical until the ship is moved to the water.
Specifications for building a ship are extensive, because meticulous attention must be paid simultaneously to a wide range of forces and stresses --- transverse strength, buoyancy, elasticity, sea water corrosion, materials quality, and the like. Once afloat and under power, the ship becomes subjected to an additional family of influences.--..tension, compression, racking, machinery vibration..--.almost unknown as to their effect on a concrete hull. In 1918 the task facing EFC engineers was to build a fleet of merchantmen made from a substance for which the scantiest design parameters had been established in accordance with specifications not yet written, all on the tightest of schedules.30
A ship or any of its kin floats, because the water displaced by its presence weighs more than does the ship and its contents. This weight is called "displacement tonnage". The weight of cargo is also measured in terms of tons, and the total is called "deadweight tonnage" -- cargo being carried earns no money and is quite literally 'deadweight'. In an average cargo carrier, deadweight tonnage (dwt) is approximately 70 to 75% of displacement tonnage (disp)31, but the San Diego tankers were 6380:7500 or 85%.32
"Gross" and "net" tonnages are, however, measures of volume, not weight. In other words, a gross ton is equivalent to 40 cubic feet, not 2,240 pounds. On a freighter, the gross tonnage refers to the space that is available for cargo, one ton usually being 40 cubic feet. Deductions are made for crew space, fuel, and stores (all necessary for moving cargo), to arrive at net tonnage.
Initial planning by EFC designers specified a wooden 3,500-ton dwt freighter. Hull measurements were to be 280' long by 26' beam with a displacement of 6,175 tons.33
While not a standard prototype Faith nonetheless set parameters used to delineate 'stone' ships that followed. She was built on longitudinal framing joining transverse frames set 16 feet apart. Lugged bars woven in a diagonal mesh were encased in concrete, the skin being part of the framing. Her bottom was 4 1/2" thick, sides 4", and shelter decks 3 to 3 1/2". There were 7 watertight bulkheads. Her principal measurements were 320 x 44.5 x 27.7. Bethlehem Shipbuilding Company of Alameda provided a 1750 hp triple expansion engine that was 24" x 39" x 65" and 42". Gross tonnage was 3,427 and net 2,071; displacement was 4,500 tons.34
Cuyamaca (ON 22022) and San Pasqual (ON 22021) had overall lengths of 434'3", breadth of 54', and a load waterline draft of 26'6". Their deadweight was 7,500, while the gross tonnage was 6,486 and net 4,082.35 Like other EFC tankers they were designed to be built of straight (not lugged or deformed) steel rods interwoven in a square lattice, 45 degrees to the horizontal. In essence, four layers of carbon steel rods on 4" centers formed the embedded net. Hull thickness varied from a 5" bottom to 4" sides and 3" upper and deck house decks.
Like others of their design, the San Diego-built tankers were 3-island hulls with a central stack, plumb stem, and counter sterns. Two masts were each served by a 5-ton boom. Both were powered by a triple expansion steam engine manufactured by Los Angeles' Llewellyn Iron Works, a vertical inverted direct-acting Stephenson link type. The cylinders were 24 1/2", 41 1/2", 72"x42" and supplied steam by 3 oil-fired Foster watertube boilers, which produced 225 psi steam on an external surface of 3,050 ft. Auxiliary machinery included for 500 gpm cargo oil pumps and anchor handling furniture.36
Cargo oil was carried in six tanks, which had a capacity of 50,000 bbl; bunkers were carried in two wing tanks. Two peak tanks and two dry stores spaces were located forward and aft. Upper deck layout included bosun/carpenter stores forward and a deck house aft that served as a crew's quarters and a hospital. Officers' rooms and a radio room were on the bridge deck.
All of the hull was concrete except for the massive stern frame casting and anchor hawse pipes. Decks were of wood above the bridge deck and on the after deck house. Forecastle house and bridge house bulkheads were likewise wood. Catwalks of expanded metal led from the amidships deck house to the ship's ends
As detailed by Bush38, building time for the hull was scheduled at seven months and another four for outfitting. Reduction of construction time was sought by continuous innovations to conventional practice...a system of shutters shunted rather than dropped the wet concrete into place to lessen splash, placement was made no higher than 18" above level of rest, and rather than rodding or tamping to increase density of the settling mass and promote liquidity, San Diego crews used pneumatic air hammers en masse to generate vibration. Desirable cohesion was achieved on Cuyamaca by blocking the steel webbing away from contact with the form.
Milton Paines Sessions, now in his 90's, was 18 that summer in 1919 when
...the first concrete ship...was built at the foot of 32nd Street. I worked up on top... receiving steel from the cranes...at an hourly rate of 75¢ to $1, if that.39
He referred to steel rodding that snaked into the interiors of wooden forms to give the hull its shape. Concrete was then ladled by power-hoisted buckets into waiting hoppers discharging into the maw of the open forms.
The concrete tanker hull was built by correctly combining wooden molds (forms) with steel rod reinforcement of a newly devised concrete. Each 7,500-ton ship called for 2660 cubic yards of concrete made with 9,400 bbl of cement. Forms consumed 1,200,000 board-feet of lumber. The net matrix was given support by 1,500 tons of reinforcing steel. Blocking and staging under and alongside the hull took another 690,000 bdft of timber.
Concrete that has set does well in coping with compressive stresses but not tensile strains (squeezing as compared with stretching). Steel, which has high tensile resilience, thereby improved the concrete in which it was embedded. Rods were placed on top and bottom of ribs and along the length of decks. In that way, hull structural members combined the quality of steel to resist tensile stress and concrete to withstand compression.
As mentioned, the shape of a concrete hull follows the planes determined by a series of molds. A form had two faces, the inner and outer, and in between there rested a fabric of inter-woven steel rods. The webbing was triced so that it could not move when the plastic aggregate flowed into the void occupying the space between the faces. After the concrete hardened and forms were removed, there stood an unbroken shell of artificial stone.
One of the special new problems with concrete hulls were "inserts", which had to be implanted in the forms before any concrete was poured. An insert was located wherever piping pierced a deck, bulkhead, or hull or in any spot where a support (such as a stanchion or a machinery foundation) was attached to the hull. Heavy machinery in the engine room and boilers were secured to grillage which in turn was fastened to bolsters set in concrete. A tanker required 18,000 inserts.
Forms were rigidly braced and were more exactly assembled than was the ordinary building construction form. Tolerances were controlled, because deviations in the volume of flow would add weight, or, contrariwise, reduce hull strength.
Another important step in forms control was a thorough cleaning of inner faces. Yard debris -- sawdust, shavings, wind-blown dirt, and paper scrap -- was prone to collect in out-of-the-way corners within the mold. Detritus lodged in intersections where frame, bulkhead, and keel met could lead to contamination and so interfere with bonding.
Forms were wetted just prior to releasing concrete. In some cases, steel was spray-treated if its temperature had risen from exposure to the sun.
Staging scaffolding provided access for workmen but also lateral stress buffering against the plastic concrete mass.
In California, form lumber was Oregon pine, a species that minimized warpage. This was an advantage in California and the dry air of San Diego, because forms might be in place several weeks before a pour was made. Facings were made of 3/4" and 7/8" plywood. The inside of the form received special attention, since there was often no more than 3/8" separation from the steel webbing. Procedural routine was such that specified hull thicknesses were attained with exceptional accuracy.
Once a pour began, work ran continuously at 8 to 15 yd3 per hour for another 3 days. As a rule, four gangs worked at the same time in four sections of the hull. Two groups were at each end of the ship, and each worked toward the middle. While they were doing that, two other gangs started at the middle and each headed either toward the bow or stern. Since placement took 75 to 100 hours, the workmen had 8 to 12-hour shifts.
After awhile the continuous pour method was abandoned. The new approach called for a removal of the top of the placement along with the laitance, and then a final pour of new aggregate was made.
On account of the narrow clearance between the steel web and the inner face, rodding and tamping did not always deliver the stiff plastic mass where it was needed. A mix too-liquid would have flowed but caused a low-strength spot. To meet this problem in San Diego, air hammers were held against the form near the pouring point. Not only did this make the mass flow better, but improved density, since the entrapped air was forced out. As many as 50 pneumatic hammers might be in use during a pour.40
Concrete was mixed on the site. A motor-driven mixer moved the wet mass to 1 yd3 bottom dump buckets carried on push cars. Cranes lifted these buckets to a hopper traveling the centerline of the ship. At points concrete was chuted to baffles for placement.
Regardless of care and attention, minor flaws formed in the hulls. Patching and pointing, however, easily corrected blemishes; withal, the San Diego yard had an extremely low incidence of remedial servicing. Accepted procedure was to evacuate a cavity and then roughen the exposed surface by hammering. After dousing the area with water to saturation, a 1:2 patching mortar was pounded in by mallet or wooden block.41
A 7,500-ton ship required 2,800 yd3 concrete with the bulk distributed about as follows:
600 in the bottom up to the turn of the bilge
1,200 from the bilge and including the second deck
800 from the second and including the main deck
200 in the superstructure
Regular concrete was too heavy for ship construction, so a new aggregate was developed to decrease weight. Translated into practical terms, a pound reduction per cubic foot gave an added carrying capacity for the ship of 32 tons, or "...a saving of 30 pounds per cubic yard represent(ed) approximately 1,000 long tons additional...carrying capacity". As a result of laboratory investigations, Wig and Hollister produced a light-weight cement of high bonding quality. Further, it was impervious to intrusion from both saltwater and petro-chemicals.42
This light-weight aggregate was developed by the Concrete Ship Section in 1918. The formula depended on a vitrified clay slurry at 106 lb/ft3 at 5,000 psi in 28 days. Watertight walls were specified 5" thick under less than a 35' head. The concrete developed could be worked into place and thoroughly embed steel webbing. This high-quality Portland cement was finely ground (90 percent smaller than a 200-mesh screen). Weight of regular concrete was reduced from 145 to between 105-120 pounds per cubic foot. The aggregate was made by burning a suitable clay to a bloating temperature. That material, crushed and screened, was augmented with a celite additive which promoted bonding. The concrete mixture was 1:2 of cement:aggregate.
The third component of the hull's construction was steel. Initial intentions were to reinforce the concrete with new billet deformed structural-grade square stock rods. For several reasons, square stock was abandoned in favor of round bar, which had been manufactured from discarded steel ingot croppings. Deformed bar was recognized for its desirable bonding values. At first, 3/8" to 1 1/4" was used, but these picked up twist when bent to conform to mold loft curves. Plain round bar 3/8" to 1-3/8", which gave low bond stress, was substituted. Another practical reason for changing stock was that steel shipbuilding requirements were answered first. Large-dimension stock could not be used because of the difficulty to bend them to specifications.
Shell bottom and side frame rods were snaked manually into the hull through access ports in the hull quarters. At lower levels, block and tackle were used to handle bundled steel. Upper levels were served by whirley cranes that rolled on tracks laid alongside the hull. Eight men were needed to put a 240'-long bar 1-1/8" in place.
Unlike other yards, at San Diego all reinforcing steel was sheared to exact length. All bars were tagged according to an erection schedule and inserted when the forms were ready to received them. Heavy frame bars were not easy to bend manually, because cold bars had a residual spring and had to be accommodated on a template or with bending dogs on a platen. Since the quality of ingot croppings varied, each bent bar had to be tested by template so as to insure the fraction of an inch tolerance dictated by design. Curves of large radius could be bent by hand, but small radii called for power-aided bending.
Except for two prototype vessels contracted to private yards, the EFC fleet was built in yards laid out for that specific purpose:
Fred T. Ley and Company, Inc., Mobile, Alabama Pacific Marine Construction Company, San Diego, California San Francisco Shipbuilding Company, Oakland, California Liberty Shipbuilding Company, Wilmington, North Carolina A. Bentley and Sons, Jacksonville, Florida
An initial set of requirements was to locate warm-water ports where speedy 12-month construction schedules could be followed. Other site selection factors for a 1200'x 2500' parcel were:
channel width and depth
regional public health
future site use
water and energy supply
Five sites were selected with the expectation that each could build at least eight vessels, which could be outfitted in situ on at least four ways.43
Outwardly, steel ship building yards share common feature with concrete ship building yards. Each EFC yard looked much like the others. In San Diego all buildings were of wooden frame construction except for those open sheds where several of the machines were housed (because of the mild weather). Ninety percent of the yard land came from dredge tailing deposits originally taken out of the new channel and the launch basin.
The yard site lay at the mouth of Las Chollas Creek, which discharged onto fine sandy loam soils. Consequently, the yard was built on Aliso fine sandy loam (Af) overlain by dredge tailings. An Af profile is described as:
upper 18" granular structure of fine sandy loam
to 4" very compact columnar clay
to 5' moderately compact cuboidal clay
beyond 5' moderately calcareous sandy loam.44
The yard site was rectangular in outline and lay on a NW-SE axis. A bench mark in the center of the proposed yard was at 32o 35.8N, 117o 45.8W. The working area was 2,000' x 450' and covered 21 acres. Plant layout is shown in Figure 7. Some of the original buildings are shown in an aerial photo some years after the site became the Fleet Destroyer Repair Base.
Atcheson, Topeka, and Santa Fe Railroad trackage entered the yard through the Bay Front Road fence between the Administration Building and the Gate House. The track divided into four spurs that ran half the length of the yard. Crane tracks were laid parallel to the basin pier face.
Ways were sloped to 3/4" to 5/8" per foot, and the ships were erected within a shipway that was 460'x78'. The launch way had to be piled somewhat differently than would have been the case for a steel ship, since the San Diego tankers were side-launched. The pile pattern was on 4' centers longitudinally and 6' transversely with the outboard rows doubled to carry the weight as the hull moved into the water. Green piling and reinforced bulkheading was used in San Diego, whereas there were regional differences at other EFC yards.
A 17'6" outfitting basin was built along the pier by removing 400,000 cubic yards of sediment. The bulk of the tailings were laid over the yard's working Two whirley cranes and a single stiff leg derrick provided waterfront service. Each whirley was 67' high and had a 5-ton reach at 80'; the derrick could lift 15-ton loads with an eighty-foot boom.
Rolling stock comprised a 250-ton locomotive, a 20-ton locomotive crane with a 50-foot boom, and 9 flat cars. Seven push cars were available for use within the yard. A 25' gasoline-powered launch served as a utility boat.
Steel bar handling machines included a bender, a wire-straightener, and two shears. The bender was a McKenna, 22 type B, useful for 1-3/8" stock and smaller. Concrete was prepared by three 24-foot Kochring mixers. A 50-air hammer array was supplied by two Gardiner 250 cfm compressors.
During construction the weight of the ship was taken up by blocking, but East Coast yards used cribbing. From a practical point, side launch is not as complicated as end launch. Stresses are believed to be kinder to the hull when launch is to the side. This was a factor that went into planning for speedier construction, of importance for war-time production rates.45
A side launch, always an awesome sight, led the hull to heel as much as 21 degrees from the vertical, as the ship appeared to roll to the basin. The first step in launching was to remove alternate rows of blocking and insert temporary blocking in their place. These new timbers were brought to bear by driving in wedges. This way, access to the bottom remained possible for inspection, initially, for minor repairs and painting. Launching way timbers were then set in place and the load of the ship transferred to them with packing. Remaining blocking was removed along with the temporary blocking.
The ship would not move as blocking was removed, because dog shores and launch keys (release devices) were placed at intervals from bow to stern. These contrivances were set fast and kept controlled by manila lines anchored to deadmen anchored inboard of the ways. On command of the launch master, the lines were simultaneously severed with a broad axe, the dog shores kicked, and the released hull slid down the ways.
Moving with wonderous lightness and speedily, the giant concrete ship slid sideways down a timber platform for about 25 feet and then, with a soul-stirring plunge, met the water of the bay.46
Cuyamaca was christened on 12 June 1920 by Miss Lucile Wilde, daughter of the mayor who was accompanied by A. P. Johnson, president of the Chamber of Commerce, E. M. Scofield, president of Pacific Marine Construction Company, Reynold J. Wig, a senior engineer in EFC, and C. L. Christie, secretary of PMCC. When San Pasqual was launched on 28 June 1920, she was christened by the daughter of E. M. Scofield, Miss Alberta Scofield. 47
Normally, outfitting begins immediately after launch, but at San Diego the ships were outfitted on their ways. Engine trials are held at the outfitting pier, and then the ship goes to sea for several days of builder's trials. Data are sought on performance and adherence to specifications. Whatever incidental difficulties show can be corrected before the ship is turned over to her owner. When Cuyamaca departed on her trials, she was under command of a now-unknown ex-naval officer, whose crew was made of shipyard employees (as is usually the case), officials, owner's representatives, and sundry observers. Steaming trials were held in early July to demonstrate she could steam uninterruptedly at 10.5 knots for 8 hours.
While at sea, the Cuyamaca had at first been unable to communicate ship's business with Point Loma's naval radio station as had been planned. The cause, it was learned, was a tidy painter who covered all bare surfaces on the bridge deck with undercoating -- including radio antenna insulators. Once cleaned, radio transmissions went without interruption.48 San Pasqual ran her trials on 14 October without a hitch.49
Reports from sea-going personnel affirmed the good sailing features of all the concrete ships. While at first opinions were sometimes less than charitable and skepticism prevailed,
The experience with the ships in service thus far indicates that they are good sea boats...these ships have behaved admirably in heavy weather.50
In a seaway rolling of a concrete ship was slower and more ponderous than that of a steel ship of comparable dimensions, a reflection of the larger moment of inertia produced on the longitudinal axis from the concrete mass "...even when loaded with cargo."51 [ed note: misprinted in the Journal and it is not clear that these figures are correct] On the other hand, in no case was the deadweight capacity of any of the ships that which had been anticipated.52
One notable and undesirable feature that concrete vessels exhibited, ships and barges alike, was a proclivity to shatter locally under impact by a concentrated blow. However, collision either from another vessel or ramming a pier, for instance, was a continuing possibility during service. On the positive side, a ruptured hull was easily repaired, comparatively, cost a moderate sum, and resulted in a negligible loss of time. No incident occurred to test the effects of torpedo blast.53
A 7,500-ton tanker cost $200-250 per deadweight ton, including the expense of experimental work, war-time wastage, and untrained management. To all appearances costs for building a concrete ship were much the same as those for a steel ship of similar dimensions. Data collected on ships in trade showed the carrying capacity was less for a concrete ship. The significant element in building, however, was that fewer expensive trades and industries were called for in a 'stone' ship. Half the total cost was in outfitting.54
A study by Fougner Concrete Shipbuilding Company, Flushing Bay, New York, reported calculated cost was $290 per deadweight ton for Cape Fear and Sapona, whereas for Selma and Latham (built in Mobile) the figure was $282. The hull of the Selma cost $786,754 with 33.1% material, 44% direct labor, and 22.9% overhead with outfitting as much again. (See Table 1). These costs were similar for a steel ship's construction during the same period.55
In round numbers, five million dollars was allocated to build the Cuyamaca and San Pasqual. A yard built for the concrete shipbuilding program cost from $830,000 to $1,000,000.56
The concrete shipbuilding experiment ended on 12 April 1921.57 Vessels under construction when the war stopped went to completion, but no new ones were laid. Although there was no question about the technological success of the program, few of the tankers and freighters went into trade. The two San Diego tankers did so, but their commercial lives were short. They gradually slipped into quiet backwaters, mostly as floating warehouses. That task served, they then became components of breakwaters around the Gulf coast.58
Early in 1920 the USSB had hundreds of steel ships on its hands. Plans were made to put them all on the market. In order to meet the outcry of ship owners and shipbuilders, a condition of sale of the few concrete vessels slated for bid was that their machinery be removed and not replaced by future owners. For that reason more than any other, concrete tankers became immediately serviceable as dumb barges or storage tanks.59 (One of these possibly became part of local waterfront notoriety when it became a gambling casino anchored off Hotel del Coronado.60
Although in trade, Cuyamaca and San Pasqual were lightly used, both sailed under the flag of the France and Canada Oil Transport Company, New York. As such, they were the only ships in the American merchant marine to have San Diego as their home port. From 18 September 1920 to February 1924, Cuyamaca sailed between Tampico and Baton Rouge-New Orleans as an oil carrier. Soon after she was converted to an anchored oil tank in Louisiana waters. San Pasqual was in company until she was badly damaged in a squall March 1921. Without being repaired, she went into layup until 1924 when she became a store ship at Santiago, Cuba, but, finally, in 1932 was dismantled.61
Both remained in the national register of commercial ships until the mid-1920's -- San Pasqual to 1926 and "Cuyamaca" 1927.62 The record then is murky...Cuyamacha may have ended either as part of a breakwater in British Columbia or a hulk in New Orleans, and San Pasqual is believed to have become a coal barge in San Francisco Bay. There is no clear evidence which of these conjectures is correct.63
On 15 February 1921, the land with the buildings and equipment that had been in the Scofield yard was transferred from USSB custody to the Navy Department and became Fleet Destroyer Repair Base.64 Some of the original buildings were still to be seen in aerial photographs, 1928 and 1939.
Post-WWI housing needs in San Diego were met, in part, by the introduction of "Rocklite", a concrete made from vitrified clay that gave a mix 2/3 the weight of regular batches.65 Was this the last use of EFC concrete tanker material?
1. Bill Durham, "Ships of Stone to Beat the U-boats," Steamboat Bill (of Facts) 19 (1962): 42; Jackson C. McNair, "America's Forgotten 'Crockery' Fleet," U.S. Naval Institute Proceedings 67 (1941): 1740.
2. San Diego Sun, 12 June 1920; 14 June 1920; 29 June 1920.
3. Jean Haviland, "American Concrete Steamers of the First and Second World Wars," American Neptune 22 (1962): 37-39.
4. F. B. Webster and others, eds., Shipbuilding Cyclopedia: A Reference Book ... Marine Equipment (New York: Simmons-Boardman, 1920), 412-626.
5. L. C. Wason and other, "Report on the Joint Committee ... Ships," Proceedings of the American Concrete Institute (1917): 505-515; Rudolf J. Wig, "Method of Construction of Concrete ships," Transactions of the Society of Naval Architects and Marine Engineers 27 (1919): 4-28; Solomon C. Hollister, "A Brief History of the Development of Concrete Boats," Wisconsin Engineer 25 (1920): 37-39; A. L. Bush, "Layout and Equipment Of Government Concrete Shipyards," Proceedings of the American Concrete Institute (1919): 216-230.
6. H. C.Turner, "Report of the Joint Committee of the American Concrete Institute and Portland Cement Institute on Concrete Barges and Ships," Proceedings of the American Concrete Institute (1918): 505-515; H. C. Turner and others, "How Concrete Ships Have Worked," Literary Digest (April 1920): 207.
7. William J. Williams, "The American Concrete Shipbuilding Program of World War I," American Neptune 52 (1992): 5-15.
8. Arthur Nilson, "Reinforced Concrete for Ships," Log of Mystic Seaport 36 (1984): 75-86.
9. Hollister, A Brief History, 37.
10. Ibid., 38.
11. Haviland, "American Concrete Steamers," 158.
12. Ibid., 159.
13. Durham, "Ships of Stone," 42.
14. Haviland, "American Concrete Steamers," 159.
15. Ibid., 166-167.
16. Williams, "American Concrete Shipbuilding," 7.
17. Arthur E. Cook, A History of the United States Shipping Board and Merchant Fleet Corporation (Baltimore: Day, 1927), 11- 28.
18. Nilson, "Reinforced Concrete," 75.
19. John A. Scott, ed., Trolleyman and Civic Record (1917), 11.
20. Nilson, "Reinforced Concrete," 76.
21. Haviland, "American Concrete Shipbuilding," 158.
22. William N. Still, "Shipbuilding in North Carolina: the World War I Experience," American Neptune 41 (1981): 188-207.
23. Haviland, "American Concrete Shipbuilding," 158.
24. Ibid., 159.
25. Williams, "American Concrete Shipbuilding," 10.
26. San Diego Sun, 12 June 1920, 1, 5.
27. San Diego (Calif.), Common Council, "Ordinance 7433 (as amended 3 August): An Ordinance Authorizing the Common Council of the City of San Diego to Enter into a Lease with the United States Shipping Board Emergency Fleet Corporation." (1918), 1-4.
28. San Diego Sun, 14 June 1920, 1; Milton P. Sessions, interview by Mrs. Mark Baldwin, San Diego, California, 1 November 1990.
29. San Diego Sun, 12 June 1920, 5.
30. Solomon C. Hollister, "Sixty-two Years Of Concrete Engineering," Concrete International 1 (1979): 63-66.
31. Rudolf J. Wig and Solomon C. Hollister, "Problems Arising in the Design and Construction of Reinforced Concrete Ships," Proceedings of the American Concrete Institute (1918): 441464.
32. H. C. Turner and others, "Report of the Special Committee on Concrete Ships and Barges," Proceedings of the American Concrete Institute (1920): 161-166.
33. S. Ina, "Concrete Ship of 3,500 Tons Deadweight Designed by Emergency Fleet Corporation," International Marine Engineering (August 1918): 446-449.
34. Haviland, "American Concrete Shipbuilding," 159; John Mariner, 'The Concrete Ship Launched," Steamship and Motorship 12 (1918): 197-198.
35. U.S. Department of Commerce and Bureau of Navigation, Fifty-second Annual List of Merchant Vessels of the United States (for the) Year Endedjune 30, 1920 (Washington, D.C.: 1920),321.
36. Wig, "Method of Construction of Concrete ships," 23.
37. Webster and others, eds., Shipbuilding Cyclopedia, plate 427.
38. Bush, "Government Concrete Shipyards," 233.
39. Milton P. Sessions, interview by Robert Eberhardt.
40. Hollister, A Brief History, 65.
41. Wig, "Method of Construction of Concrete ships," 18.
42. Ibid., 14.
43. Bush, "Government Concrete Shipyards," 217.
44. U.S. Department Of Agriculture and University Of Cnlifornia, Agricultural Experiment Station, Soil Map (of the) El Cajon Area, California, Scale 1:62,500. (Washington, D.C.: 1920).
45. Bush, "Government Concrete Shipyards," 219.
46. San Diego Sun, 12 June 1920, 1.
47. Haviland, "American Concrete Shipbuilding," 162.
48, San Diego Sun, 12 June 1920, 8.
49. Haviland, "American Concrete Shipbuilding," 162.
50, Turner and others, "How Concrete Ships Have Worked," 207.
52. Ibid., 162.
53. Nilson, "Reinforced Concrete for Ships," 82.
54. Turner and others, "How Concrete Ships Have Worked," 163.
55. Haviland, "American Concrete Shipbuilding," 165.
56. Bush, "Government Concrete Shipyards," 230; Jerry MacMullen, 'The Roseville," San Diego Union, 22 December 1957.
57. Haviland, "American Concrete Shipbuilding," 162.
58. Jean Haviland, "U.S. Concrete Ships," Sea Breezes 26 (1958): 72-73.
59. Nilson, "Reinforced Concrete for Ships," 84.
60. Richard Crawford, "The Gambling Ships of San Diego," San Diego History News (June 1985): 3.
61. Durham, "Ships of Stone," 43; Haviland, "American Concrete Shipbuilding," 72; San Diego Sun, 12 June 1920, 8.
62. MacMullen, "The Roseville."
63. Haviland, "American Concrete Shipbuilding," 73.
64. W. C. Mattox, Building the Emergency Fleet (New York: Library Editions, 1970), 76.
65. MacMullen, "The Roseville."
Robert Eberhardt is a retired fisheries oceanographer who has been a part of the San Diego waterfront scene since the late 1930s. He and his family moved here permanently in 1970. He was then employed as an industrial scientist and, later, community college professor in a maritime training program. He has published several studies in maritime history relating to local topics.