maritime

"There is a small light exhibited on each of the pier ends: Port Said Lighthouse itself stands at the inner entrance of the western . It is a grey-colored octagonal-shaped tower, constructed of concrete, 180 feet high, exhibiting an electric light visible at a distance of 25 miles, and it forms a noble beacon by day or night."

"On the following morning, the 22nd, I climbed to the top of the lighthouse of Port Said. It is one of the highest in the world—160 feet high—and its electric light is visible at a distance of twenty-one s. Its strong walls are built of blocks of the same concrete as the mole of the harbour—immense cubes of artificial stone, composed of seven parts of desert sand and one part of French hydraulic lime. The view from the top did not in any respect answer my expectations, for, beyond Port Said itself and its immediate neighbourhood of flat sand, nothing is to be seen but water on every side."

"So he walks the path at nightfall with a bundle in his hand. Into a nest of cedar bark and twisted grass he lays the coal and feeds it with his breath. It dances and then subsides. Smoke pools darkly as the grasses melt to black and then erupt into flame, climbing one stem and then another. All around the meadow, others do the same, setting in the grass a crackling ring of fire that quickens and gathers, white smoke curling upward in the fading light, breathing into itself, panting across the slope until its convective gasp sets the night alight. A beacon to bring their brothers home."

"Founded on rock and facing the night-fouled sea A beacon blinks at its own brilliance, Over and over with cutlass gaze Solving the Gordian waters ..."

"The beacon-blaze unsheathing turns The face of darkness pale And now with one grand chop gives clearance to Our human visions . . ."

"Modest doubt is call’d The beacon of the wise, the tent that searches To the bottom of the worst."

"[F]errocement ...uses wire mesh, rather than heavy rods or bars, as the primary part of its metal reinforcement and which uses sand [in a mortar mixture] rather than a mixture of sand and stone ...as the aggregate in its concrete mix. ...The resultant product can be a shell of surprising thinness, durability, resilience, and, when properly shaped, strength."

"The domes were very easily repaired by replacing the damaged mortar or mesh..."

"Ferrocement is used relatively little in the housing field because it is regarded as a labor-intensive... building technique. ...It is true that considerable labor is required to put together... sand, cement, and wire mesh... However, the elaborate temporary framework which consumes most of the labor in conventional work is often entirely eliminated... Even if we concede that ferrocement is impractical where labor is expensive... its use requires only time, not skill..."

"Ferrocement is a form of reinforced concrete... [utilizing] closely spaced multiple layers of mesh or fine rods completely embedded in cement mortar. It can be formed into thin panels or sections, mostly less than 1 in. (25 mm) thick... Unlike conventional concrete, ferrocement reinforcement can be assembled into its final desired shape and the mortar... plastered directly in place without the use of a form."

"Portland cement is generally used, sometimes blended with a . The filler... is usually a well-graded sand capable of passing a 2.36 mm (No. 8) sieve. However, depending upon the... reinforcing material (mesh opening, distribution, etc.), a mortar containing some small-size gravel may be used. ...Addition of short and discrete fibers of different types favorably affects the control of cracking and the capacity... to resist tensile loads. ...[R]elatively short and slender (l/d = 100) steel fibers may be randomly distributed in hydraulic cement mortars... the overall effect being to increase tensile strength and improve the shear resistance..."

"Chicken wire mesh was recommended because of its ductility. It shows no oxidation problems as it is made with galvanized wire. It has reliable properties and is low in cost."

"[T]he ferrocement roofings are practically waterproof and that they do not need any special treatment."

"The structural effectiveness of any reinforced concrete, including ferrocement, depends on the almost miraculously fortuitous fact (first discovered in 1870 by ) that steel and concrete have close to identical coefficients of expansion, swelling at exactly the same rate when heated, shrinking at exactly the same rate when cooled. Thus they may be permanently bonded together as a single material, utilizing the best structural characteristics of each: steel has the tensile strength... while concrete has the ..."

"Nervi's first used of ferrocement in an important public structure was in the 1948 Exposition Hall in Turin. ...The great corrugated roof is... ferrocement panels 1 1/2" thick tied together by ribs of conventional poured concrete..."

"Most of the more recent use of ferrocement have been by others, but it is to the insight and pioneering work of that they owe their successes."

"[B]y the end of 1943 Nervi's firm was at work on three 150-ton transport boats, their hulls completely of ferrocement, and one 400-ton vessel, largely of ferrocement. The first construction was interrupted by the war, and it was not until 1945 that Nervi's method resulted in... [t]he Irene... a motor boat with a 165-ton displacement. On a supporting frame of 1/4" steel rods spaced about 4" apart, Nervi spread eight layers of wire mesh, four on each side of the rods, which were tied tightly together and plastered by hand with a rich cement mortar. The resultant ferrocement was 1 3/8" thick (about the same thickness as Lambot's boat). Other than the rods sandwiched into the mesh, no formwork was needed."

"[B]ecause of its intrinsic hardening process which continues indefinitely, good concrete gets better and better, imperfect concrete (with flaws that invite erosion and corrosion) gets worse and worse."

"[T]o increase the load capacity of the domes and to avoid excessive deformations, it is necessary to provide the best possible anchoring at the edges."

"In the 1953 Milan Fair building and in the 1959 Flaminio stadium... Nervi used ferrocement corrugations... in strikingly cantilered roofs. A further use by Nervi of the material has been in... smooth, lightweight forms into which conventional poured concrete could be molded..."

"[A] dome of any shape will amply comply with safety requirements. Because of this it is believed that it is possible to build domes in situ without specifying the shape of the dome, which makes skilled labor unnecessary."

"[T]he early work of Lambot... was one of the first applications of , but [was] also... a form of . His patent on wire-reinforced boats that was issued in 1847... This was the birth of reinforced concrete, but subsequent development differed from Lambot’s concept. The technology of the period could not accommodate the time and effort needed to make mesh of thousands of wires. Instead, large rods were used to make what is now called conventional reinforced concrete, and the concept of ferrocement was almost forgotten for 100 years."

"In 1947 [Nervi] built his first ferrocement structure on land, a storage warehouse... 35' x 70' and all four... walls [and] roof were of ferrocement 1 3/16" thick, their thinness made structurally feasible by their corrugated shapes."

"All ferrocement can be said to be , but all types of reinforced concrete are not ferrocement."

"[F]erroconcrete would be a more accurate term for our material, but that term is already in common use to describe... reinforced concrete work."

"[F]errocement... may eliminate the need for separate layers of waterproofing."

"[A]t the new ... [the] famous sail-shaped roofs (built of conventional reinforced concrete) have been covered with tile-surfaced panels of ferrocement which serve as waterproofing..."

"The purpose of this book is to match an existing resource with an existing need. The need is shelter... simpler structures... that can be assembled quickly in the wake of a hurricane or flood... that can be built economically in undeveloped countries... that... provides pleasure in the form of self-made personal retreats..."

"Although... two of the first patents for reinforced concrete of any type... were for ferrocement, that particular type of reinforced concrete was generally underutilized—in fact, forgotten—until 's work of the 1940s. ...The turning to ferrocement... was based on the logical use of a known fact: the structural behavior of reinforced concrete is most effective near the points of its reinforcement. ...Nervi was first to ask the question... why not distribute the metal reinforcement so evenly that all the concrete is in immediate proximity to it? On this theoretical foundation Nervi performed the experiments which led to his establishment of ferrocement building technique as we know it today."

"[B]efore... crude beginnings of work with conventional reinforced concrete, work with ferrocement had already begun. ...The ferrocement technique seems to have been first used by ... and, apparently... independently, by ...Jean-Louis Lambot. ...Lambot called his invention "ferciment" and used it to build boats... He constructed his first boat in 1848..."

"The following year Nervi designed and built a 41' ... the Nennele... the hull's total thickness was less than 1/2"."

"Ferrocement... often acts more like steel than like a standard reinforced concrete. Hit with a hammer, it rings like a bell."

"This highly specialized, but by no means highly complicated building technique had been almost forgotten after its first use... in the middle of the nineteenth century until it was virtually reinvented in the 1940s by... ."

"An alternative construction method was also developed which did not require the use of any type of mold or form."

"The curing of the shell is achieved by covering the surface with wet sand for a period of 72 hours."

"The best solution found was to form a double curvature surface... The curvature does not necessarily follow a pre-determined law, so that it may be checked roughly "with the naked eye"."

"The mortar used for the mix is made (using a mixture) of normal or ic cement and sand in a proportion of 1:1.5 by volume and with a water-cement ratio of 0.55."

"The reinforcement consists of two no. 2 bars along the edges, one of them straight and the other one with the necessary bends to provide the handles to lift and fix the dome to the structure. ...[T]wo layers of galvanized chicken wire, guage 22 with a separation of 13 mm are attached to the bars and directly mounted over the mold, one perpendicular to the other. ...[E]nsure a minimum overlap of 5 cm... and... ensure that these are stretched... to achieve the thinnest section possible."

"After a couple of hours, the desired finish is applied (polishing or brushing), with the object of sealing the cracks or faults that may appear on the surface of the dome."

"[T]he smaller the thickness of the cover, the better will be its quality, which is why at the time of pouring, the meshes of the wire should be well stretched. Care should be taken that only enough mortar to cover the reinforcement is used."

"[I]t was decided to develop a type of roofing based on prefabricated sections. ...With the partial results obtained in this stage, another part of the study could be initiated, i.e. to build this same type of element "in situ"... thus providing solutions for situations in which prefabrication is not appropriate..."

"Ferrocement was chosen as the material for the proposed roofing because of its physical properties (strength in compression and tension, impact, permeability, etc.) and because it is cheap and easy to build."

"The adaption of ferrocement precast roofings in self-help construction projects... permits the use of standard components which are easily erected without sophisticated equipment."

"The hull was left untouched for 18 hours after the plaster finishing work had ceased. This allowed the hull to set-up hard enough for the men to drag the steam tent over it. It is not advisable to start steam curing too soon, as the jets of hot water from the steam pipe may wash some of the mortar off the hull while it is still green. Before steam curing began the wooden screeds were removed from around the hull sheer."

"The mortar used for the hulls was a mixture of clean, graded silica sand, ...Portland Cement Type II, and drinking-type water. This silica sand, of the grading and particle shape used in high-strength structures... The sand content used was... one 50-pound (22 Kg) bag of coarse grade, one 100-pound (44 Kg) bag of medium grade and one 50-pound (22 Kg) bag of fine grade. To this graded sand was added two 80-pound (31 Kg) bags of Portland Cement Type II and just sufficient water to make the mortar workable into the hull mesh reinforcing. ...There was one plasterer for roughly every 100 square feet (9 m2) ...Retarders or additives were not used. The sun shelters were moved into place ..."

"The last four layers of mesh were stapled to the hull mold. They were laid in the same way as the first layers. The mesh was fastened... as smoothly and as tightly as possible. It was clipped onto the horizontal rods with 3/4-inch (19 mm) hog rings. ...One-half inch (12.7 mm) hog ring staples which do a neater job could not be located ...All edges of the mesh were stapled down tightly so that no stray ends of mesh would penetrate later through the fresh mortar and thus interfere with the plasterers' work... Mesh over the chain link scuppers was clipped away and the ends fastened down neatly."

"First a heavy coat was applied all over the hull. Men stationed inside the hull mold began systematically vibrating the mold planking and checking the gaps between the planking for mortar penetration. Once the mortar had all been applied to the satisfaction of the men vibrating and checking, the excess mortar was then scraped back to the mesh. ...A new thin coat was troweled over the hull and allowed to start setting. When it started to set the hull was sponge troweled, the sponge trowel being used in a circular motion to smooth out surface irregularities. As soon as the sponge troweling was finished, the final steel troweling began. This was carried on until the hull surface had set up too hard to be worked on any further, and was as smooth and fair as the plasterers could make it."

"[These] low cost, easily built, high quality ferrocement roofings... offer an innovative solution to the serious dwelling problem affecting large numbers of people, especially in the marginal urban areas and rural zones of developing countries..."

"The hulls were steam cured for 24 hours at a temperature of 150°F (66° C). A steam pipe, perforated for its entire length, was placed under the inverted hull and a rubberized canvas steam tent drawn completely over. The temperature was carefully brought up to 150°F (66°C) in a period of four hours. Twenty-four hours were then maintained at this prescribed temperature until, finally, it was allowed to drop slowly to ambient temperature of 85° F (30°C)."

"The construction of the mold simply consists of making a dome of well compacted earth, covered by a layer of well-finished concrete having a thickness of 8 cm [3.15 inches], with the shape defined by the trusses... used to [shape] the mold."