About that Boat - Noah's Ark

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Pouring this much water onto the surface of the Earth, from whatever source, will produce hurricane-like condition.

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Pouring how much? You seem to be under the impression that the Biblical Flood was caused by rain alone. (What is that? Sunday School misinformation again?)The Bible mentions two other ingredients involved in causing the Flood: 1. The break up of the fountains of the great deep, and 2. The opening of the windows of heaven. Neither one of them need have anything to do with rain.I am not saying that there was no wind at all, but the Bible says that the big winds did not start until after the Ark was already ashore. That evidence alone should tell you that what ever the Flood was, it wasn't just another rain storm, or hurricane.

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How do you pump several million cubic miles of water onto the surface of the planet and maintain New York Central Park boating conditions?
Answer: You don't.
The only way you could possibly have no wind and flat seas is to have ZERO temperature / pressure gradient differences on a global scale and at all elevations, both above and below the water surface, 24 hours a day.

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I never said that there was no wind.
I never said that the seas were flat.
I mearly pointed out that high winds did not begin until after the Ark has already landed. Which indicates that whatever the flood was, it wasn't just some kind of unstable atmospheric disturbance such as a typhoon or hurricane or whatever.To be sure there was rain, but that was not all. The breakup of the "fountains of the great deep" may be a reference to somekind of geologic disturbance that disrupts the status quo. The 'Windows of heaven' may be a reference to cosmic influence of some sort. It is possible that the flooding may have been more the result of tsumai run up rather than rain.

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I would love to see the model of what lunar tides would be like with no land to impede the tidal surge as it races around the globe twice a day.

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Who knows, that may have occurred.

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Why do you focus on tension and compression? Those are only two factors. True. The top and bottom will carry a high compression and tension loads. This is not the end of the calculation.

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Yes, they are only two of the forces but they are important ones. "Under most conditions of loading, the worst stresses in a beam are imposed at right angles to the direction of loading... Failure may also occur because of what we call shear... I don't indent to say much more about shear failure because bending moments rightfully demand the most attention in ship desin." Benford, Harry, 1991, "Naval Architecture for Non-naval architects," Published by the Society of Naval Architects and Marine Engineers. (SNAME) p. 140.I also calculated the shear forces for a box-girder design Ark and as you remember they are quite small. I have focused most on the bending moments because those are the largest stresses any ship will encounter. If SNAME doesn't know what is the most important stresses then heaven help all ships at sea.

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All of this has been static load? How can you pretend to compensate for waves by calculating static loads?

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The formula I've been using are for the standard l/20 trachoidal wave stress. This is concerned primarily with the bending moment and shear stress. Shock and torsion stresses, AKA impulse wave loads, are typically of short durationa and referred to as transient loads. But the magnitude and distributions of these loads, however, remain uncertain. This nonlinear effect may significantly change the distribution of the longitudinal bending moments and shearing forces. Major classification societies have either approximated this nonlinear effect in the rules or require additional calculations. (from Taggart, R. Ed. 1980, Ship Design and Construction, pub. SNAME. pg 239) So that's why I am looking for the formula to calculate these forces.

I said: "As long as differences in construction methods are adhered to, it is possible to scale up from steel to wood."
You Said: "So you DO believe it is possible to build a wooden ship of any size whatever if we just use enough wood?I didn't say ANY size, but rather that it is possible to design a wood ship to same size as a steel ship by adjusting the cross-sectional area to match the strength capability of wood. I am not the only one to think so.From, Donnelly, W.T., 1917, Problem of the Wooden Cargo Ship: Description and calculations relative to construction of a 5500 ton deadweight carrying capacity cargo vessel, Marine Engineering International. 22(5)206-211:"The plans and information submitted herewith relative to a wooden ship of dimensions and carrying power much beyond anything hitherto constructed are the results of many years given to the sutdy and investigation of this problem...."The writer's attention was directed to the problem of the wooden ships by investigations and developments in the application of wood to floating dry docks, which in the last twenty years has resulted in the building of these structures up to a carrying power of 20,000 tons."The problem as here presented is believed to be a thoroughly scientific and practical solution of the use of wood as an engineering material for ship construction, and the plans as here presented have received very careful review and criticism by engineers of the highest standing."The vessel shown in the plans (sorry can't show them here) is 350 feet long between perpendiculars, 50 feet beam and 30 feet molded depth, with a deadweight cargo-carrying capacity of 5,500 tons. ... In these figures will be seen a typical secton of a steel double bottom ship of similar dimensions to the wooden hull under consideration ..."The longitudinal deflection diagrams give information relative to the strength and rigidity of the hulls. In working these out I have used the modulus of elasticity for steel of 30,000,000 and for wood 1,500,000 pounds."For the steel hull the deflection was worked out to correspond with a miximum stress of 10,000 psi, upon the material of the midship section, and was found to be 3 inches; and then a similar calculation was applied to the midship section of the wooden hull to determine the stress psi for the same deflection, and this was found to be 600 pounds."In comparing these results, it sould be noted that a working stress of 10,000 psi for steel compared with an ultimate strength of 60,000 psi gives a factor of safety of 6, while a woking stress of 600 psi applied to wood as compared with an ultimate strength of from 8,000 to 10,000 psi give a factor of safety of something more than 12."From twenty years' experience in the design of floating dry docks, I am prepared to state that I have found it entirely practical to develop as near an approach to the full section value as is possible with steel.
End QuoteSo. This experienced naval architect and engineer shows that it is possible to design a wooden ship the same size as a steel ship and be able to successfully withstand the stresses.And then there is this from Benford, H. 1991, Naval Architecture for Non-Naval Architects, Publisher SNAME, p. 155.From a section on construction materials -- Wood;"One of its historic shortcomings was the practical difficulty of making efficient end connections. In former times this technical fact tended to limit boat lengths to the length of available lumber. Greater lengths were possible, but always at a price in strength and complexity. This is no longer true. Modern fastening devices and bonding materials... have freed wooden hulls from the constraints of the past. Joing efficiency, which in bygone days was perhaps only 25 percent, may now be as high as 85 percent. Still we do not see ships of any great size being built of wood because, even at best wooden hylls become relatively heavy and expensive as size increases. Moreover, as the world's supply of timber continues to shrink, the availability of suitable lumber becomes a worsening problem.
end quoteIts not size that is the problem for the construction of wood ships, it is jointing and economics that is the problem. Economics evidently was not a problem for Noah, because he built one. And somehow he solved the jointing problem, perhaps by using full length structural members.Allen

I Said: The opening of the windows of heaven.
You Said: How can this not mean "rain"? Where is heaven if not up?What has the "opening of the windows" have to do with rain? And just what is meant by "windows of heaven" anyway? It is interesting to find that the Hebrew word that is translated as window is elsewhere translated as Chimney, Dove Cote, and Lattice. Besides that, the root verb from which this Hebrew word is derived means "to ambush." How do you get a noun derived from "to ambush" to mean window, lattice, chimney or dove cote?? While other words derived from the same Hebrew verb mean "an ambush," "an ambusher," or "attacker." There is something more here than immediatly meets the eye. Rainfall is hardly an adquate result to tie to the opening of the windows of heaven.So what if heaven is up? So is the sky, the stars, comets, asteroids, galaxies and outer space. (Of course there are some who will argue that when we use the word "up" we should really use the term "out" or "away.")Allen

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If you won't take it to mean "rain", then you have to take it to mean literal windows in the sky, which are obviously impossible, and would thus falsify the flood account. Or otherwise you have to explain what you think that means. It has to mean something, or else it wouldn't be there.

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I dont want to take too long on this, because we are getting off the topic of the Boat and it's design and strength, etc.Getting back to the hebrew word again -- "arabah." who's root is "arab" which means "to ambush." I believe that the key to understanding the meaning of the word and its relationship to it's root is found in the translation "lattice". In the Middle east. Chimneys often have lattice work that cover the holes. Windows are usully covered with intricate lattice work shades. Thus the women who are not allowed to be seen, can see out the windows without being observed. And a dove cote resembles lattice work in its general shape.
The lattice work windows can tie into the general theme of ambushing, or lying in wait, by noting that an attacker can hid behind a lattice window watching for a victim and yet not be seen. When the victim is within range, the attacker would then open the window and attack the victim. The victim would not see the attacker until the window is opened and the attacker jumps out.If we apply this concept to the opening of the windows of heaven, then there would be something not visible lying in wait to attack in the heavens. It would only become visible as it attacks from the heavens.One might relate this to rain, but rain doesnt come from a cloudless sky.Creationary Cataclysmists are looking to something else for which there is found evidence in the gologic record. Bolide impacts. Asteroids are invisible to the naked eye, and the first indication that an impact is going to happen is the 15 seconds it takes for one to streak through the atmosphere before impact. The results of such impacts are catastrophic -- fire storms, earthquakes, impact-tsunami, etc. If, as Creationary Cataclysmists believe, the geolgoic record is of the Flood, then hundreds of bolides impacted the earth throughout the Flood. Such a "storm" of asteroid impacts would certainly be an ambush through the windows of heaven. And not be rain.Allen

Alright! A good start!

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This is almost never done in tank tests, so testing is done on computers. Do you have any computer modeling data to share with us?

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I have a preliminary design that I've been working on, but nothing that would be ready for computer modeling. It depends upon how detalid a design is needed. I'd love to do that, but I just haven't gotten that far yet.

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I used the Seine River barge design as the model. These are almost totally rectangular, with a small amount of curve in the bilge and a bit of rounding at the ends.

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I looked up some photos of Seine River barges. They apear to be open top barges based on the keel/rib design. I see that the scantlings make no mention of a top deck. This emphasizes the idea that the keel although nearly 12 feet wide but only some 5 feet high, is designed to deel with all the forces. This is like laying a 2x4 flat between supports and expecting it not to bend much when someone walks across it. Such a design is doomed to fail. The only possible way to attempt to save the design is to try to incorporate the sides of the design into stress bearing members. However, as was mentioned before, most ships built on the keel/rib design consist of a keel with a bunch of reeds poorly fastened together. That's where this design seems doomed to follow.I was curious if dimentions of the frames and planking were computed from the supplied over all dementions or did you put those numbers in yourself?Allen

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The scanlings number, cube root of the displacement in cubic feet, is the scantlings number which is entered into the formula.

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Ahhh. yes. that is what I thought, I just wanted to make sure. The reason I wondered is because the numbers you got for the ribs (~23 in.)and planking (~24 in.)--double planked -- is fairly close the the measurements I was using of 1 cubit (~21 in.)for plank thickness and frame member thickness

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It is not just the keel, but all the longitudinals, as well as the planking, that gives strength. (Crushed deck beams will compromise the entire structure.)

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Do you remember the quote John posted (see page 3) about analyzing wooden ships? it says:

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A wooden ship, especially as it ages, more closely resembles a rather weakly bound bundle of reeds. These reeds are free to slide past each other. ... Failures in longitudinal structure are infrequent and tend to be scattered almost uniformly throughout the vessel. The idea of "strength decks" or "extreme fiber" is largely irrelevant to the meaningful analysis of old wooden ships. Microscopic investigation reveal a generally low level of stress...
http://www.tricoastal.com/woodship.html

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According to this quote, because the planks function like "reeds that are free to slide past each other" and because they experience a 'generally low level of stress' then they can add little to the overall stress bearing capacity of the ship. This means that the major part of the stress must be carried by the keel. And in this case it is like a 2x4 layed flat. This ship would not just hog and sag it would ripple.However, if you were to fasten all the planks to each other such at they are not free to slide past each other, then you have another proposition altogether. In this case, The planks would then take on a large portion of the stresses. The ship would then behave like a box-girder.

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The deck specs were included.

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Ah, yes, I was looking for other teminology so missed it. If the top deck were constructed like the rest of the ship, and the planking fastened such at the planks could not slide past each other, then such a top deck would greatly increase the stress bearing capability of the ship.You said these were your "first calcualtions" is there more to come?

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... you may be the only one since 1917.

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perhaps...

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I haven't seen any proof of his theories.

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Hmmm. let me see. Whom should I think knows more about what he is talking about?... A vetern Naval Architect with over 20 years of experience at that time desiging and building wooden floating dry docks that could lift vessels 1/2 the size of Noah's Ark, and who submitted his plans and ideas to his peers, i.e. Naval Engineers, for approval. Or, a carpenter with 10 years experience. Gee, that's a tough call.

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By the way, where are those really big trees?

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Just down the road from here is Petrified Forest N.P.. I've measured some of the long logs at near 120 ft. The butt ends of some were 4 ft thick and the other end about 2.5 ft. Also in the area are stumps that measure over 6 feet across.

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Under most conditions of loading, the worst stresses in a beam are imposed at right angles to the direction of loading...

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This statement, within context of diagrams in the text which I was not able to reproduce here, notes that the loading force is vertical and the stresses are normal to the loading force and lengthwise in the beam, not crosswise to the beam. These are the typical compression/tension stresses that a loaded beam experiences.

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Also, I notice that the author is discussing beams, not the whole ship.

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Again, the full context is a discussion of the whole ship as a beam.

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Again, your are failing to consider the differences in materials.
What happens when you bend a nail? It bends.
What happens when you bend a toothpick? It breaks.

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You cannot just take the material into consideration, you must also take into consideration its dimensions.
Take a 10 penny nail (3 inches long and 0.0157 in. in diameter) and apply a force to bend it.
Take a wood dowel 3 inches long and 0.0157 in. in diameter and apply a force to break it. That force will be approximatly 1/6 of that needed to bend the nail.
However, it will take approximatly the same nail-bending force to break a 3 inch long, 1 inch diameter wood dowel.
In the design of a wood ship, the stress bearing members are increased in cross-sectional area to match the expected forces just like we used a 1 in. diameter dowel to equal the force needed to bend the nail.

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I said: I have focused most on the bending moments because those are the largest stresses any ship will encounter.
You said: Maybe you need a primer on stress.

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Maybe I just need to listen to those who know what they are talking about...

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I don't indent to say much more about shear failure because bending moments rightfully demand the most attention in ship desin.

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This site has done a lot of design work for an Ark sized wood vessel. The Flood | Answers in Genesis Allen