US2389353A - Floating dock - Google Patents

Description

. @www Nov. 20, 1945. H. o. Foss 2,389,353

FLOATING DOCK w Filed April 14, 1945 2 Sheets-Sheet 1 7. Hayley 0.25666 NOV. 20, 1945. H, O, F055 2,389,353

FLOATING Doux Filed April 14, 1945 2 sheets-shet 2 www Patented Nov. 20, 1945 UN l TED STATE S PATE NT OFFICE FLOATIN G DOCK Henry 0. Foss, Tacoma, Wash. ApplicationApril 14, 1943, .Serial No.-483,022

7 Claims.

This invention relates ,to loating docks 'and similar structures. y

As is well known, it has lbeen the common practice to build many types of docks by employing conventional piling driven into position. Such piling has been employed for supporting wharves and for Vforming ferry boat slips substantially fitting one Vend of the Vferry boat to guide it into position. Ordinary piling is open to several objections in actual practices and .this is particularly true of the luse of piling for forming ferry boat slips. 'In the rst place, the piling has no support between `the bottom of the water and the point at Which forces gare trans-y mitted at right `angles thereto by boats moving into landing position. This is particularly vdisadvantageous whereferry boat slips 'are built in relatively deep water, as is often necessary.

Inasmuch as forces are exerted against the piling at points remote from the points of support thereof, the piling are subject to be being .broken oi at the ground. Piling employed in salt water is subject to attack by marine borers, such as teredos, andaccordingly the piling has .very limited life. In actual practice piling used in salt water will not last over six months because of the weaking and breaking of the piling due to the action of marine borers.

Whereipiling becomes broken .at the ground line, fit is .impossible to replace it with piling driven in the `same position .due to the impossibilityy of removing Athe lower end lof the lpile from the ground.` Ilius substantial .diiculties as well as great yexpense are involved in maintaining pilingfand particularly those used as ferry yboat slips.

It is wholly impracticable to employ oating docks such as ferr-y boat slips by .securing -them by means .of anchors. As is well known, it is impossible to moora boat to an anchor by means of a short chain yor .cable Vsince the `forces `transmitted to the anchor are largely vertical and will ndislodge 4the anchor. It is therefore well known that the mooring of boats `and Vbuoys requires relatively long lines in order that the forces transmitted to the anchor may be largely horizontal vwhereby Vthe anchor will hold against dislodgment. The Ause of Isuch long lines renders it wholly -impracticable to x floating docks in position by such means. n An important object of the present invention is to provide a novel oatingdock construction which eliminates the disadvantages of the use ofA vpiling and serves to hold the `dock relatively stationary without the use of conventional anchors? A furtherzobject ,is to 'provide a noo/'e1 dock construction wherein a iloating dock Iis employed and is held Yin Aposition :by vmeans :of chains or the like connected to piling .sunk whollybe'neath the `surface of the ground 'where Ait is protected from borers vand is not .subjected 1to `unsupported strains exerted Vagainst theA piling ytransversely thereof.

A further object is to provide ysuch a :oating dock which is effectively heldin position against any reasonable strains `which might rbe exerted thereagainst while at the'same :timev cushioning y the landing of a boat, rthus minimizing damage to the boat and dock.

A further .object to provide a 'lloatin'g -dock having 'novel means :for holding zit in position whereby it remains relativelyaccurately in position :regardless o1 windtides, etc.'

In the drawings I have .shown -two general embodiments of the invention. In this showmg .i

Figure 1 is a plan view of a Vdock lay-out,

Figure 2 is 'a front elevation of the same,

Figure 3 is a vertical sectional view showing a pile, in elevation, arranged ready to -besun'k in the earth,

Figure 4 is a similar in'position,

Figure 5 is a similar `view showing the `driven pile vwith the upper 'end removed 'therefrom and with the chain connected `to a portion of a il'oatY ing dock,

Figure 6 is a plan -view of a modied type of dock lay-out, and

Figure 7 is a perspective View `Aof one Uof Vthe buoys employed in Figure 6.

Referring to Figure 1, the .numeral l0 designates the ground adjacent a body of water' H, the shore line being indicated bythe 'numeral' l2. A floating dock I3, to 'be referred to later, is arranged preferably `relatively vclose to vthe shore line. LA conventional Vapproach `to the fdock is indicated by the vnumeral M and an apron 15 has one end connected to the approach and its opposite end bearing on the top ofthe dock +3. The apron l5 is of such nature as to permit its dock end to move upwardly and downwardly as the tide ebbs and flows.

In the present instance the dock I3 has been shown as being of a truncated V-shape to serve as a slip to receive an end of a ferry boat, shown in outline in Figure 1 and indicated by the numoral I6, It will become apparent that the inview showing a pile driven vention is not limited to a ferry boat slip but Y provided with mooring chains i8 which diverge.

from eachother toward the dock. At its land end, the rock is shown as having its opposite corners connected to mooring chains I9 which may sharply diverge toward the shore line. The..

dock may also be provided with inside mooring chains extending toward each other away from the shore line.

The number and arrangement of mooringl chains wil1 depend upon the type of dock, conditions at the place of installation such as tides,

etc., and the size of the dock and the size of the boats intended to land at the dock. l

The various mooring chains have theirlower ends secured to a novel type ofpiling shown in finished form in Figure 2. yThe method of installing the piling is shown in Figures 3, -4 and 5, and reference is made to these figures. A pile indicated as a whole by the numeral 2l is grooved intermediate its ends' as at 22 to provide a lower anchoring end 23 and an upper end 23" to be later removed in a manner to be described. Near the extremity of the pile end 23 one end of a flexible element, preferably aheavy chain, 24 is turned around'the piling, preferably'twice, and half hitches are taken in theV chain to insure a permanent connection of the chain to the pile. The end of the chain is secured to the pile by a bolt 25 extending: through the pila/and the half hitches and the turns of'thechain about the pile tend to cause abinding of the chain about the piling without 'transmitting undue strainsto the bolt 25. Y ,J j .The pile is placedin position as shown in Figure 3 in a vertical position with the lower exi tremity of the end 23 resting on the bottom'or surface of the'earth 26. The pile'will`be placed and held in such position with respect to a pile driver by which the driving of the pile is ready to be effected in the customary manner. #The free end of the chain 24- will be supported at some point on the pile driver in any suitable manner. The pile is then driven into the bottom 26 until 'the groove `22 is at a level slightly below the surface of the bottom 2,"as shown in Figure 4. The cutting of the groove 22" will not interfere with the 'transmission' of vertical thrusts through the pile to sink the `lowerend thereof Vinto `the -earth. However; the groove weakens the pile and permits' the exertion of a transverse strain -to theT upperend of the pile to break it' oif in the planegof th'e'groove 22.v This operation is performed andthe'upper end 23' ofthe pile is then removed.

`While the removal of the upper. end of the pile' provides access of the water to the upper extremity vof the 'lower pile erid23, it will be ob`" vious that'the earth will soon shift and will 'completely cover'the pile as shown 'in Figure 5. The pile end 23 thus becomes a permanentpile completely 'embedded in the' earth and protected against the action of marineborers. I v

With the float in position and a suflicient number of properlyplaced permanent Vpiles driven into the earth, the chains of the, respective piles maybe connected by any suitable means tothe properf points on the float. Each chain Z4 b- Vup of a plurality of floats or buoys. Referring to Figure 6, the numeral 28 designates an approach having an apron 29 connected at one end thereto. InY this type of installation, wherein a number of relatively small floats are employed, it is impracticable to employ an apron having a vertically movable end as in Figure 1. Accordingly the dock end of the apron 29 may be supported in any suitable manner, as by means of n posts 3G driven into the ground.

The ferry boat slip shown in Figure 6 may be made up of a plurality of floats 3| arranged parallel to each other. Each float is provided with at least four mooring chainsS, and these chains may be angularly arranged relative to each other and relative to the float. For example, the chains vmay be arranged radially with respect to the center of each individual float, or they may diverge from each other at other angles, depending upon individual conditions of installation. At least the outermost float 3l is preferably provided with an additional mooring chain indicated by the numeral 32 and this chain may be arranged parallel to the adjacent chain which extends inwardly from rthe inner corner of the float at the side thereof remote from the shore. This arrangement provides greater stabilityfor the floats which take the maximum thrustswhen aboat is landing, as will be apparent.-

Each float 3l ispreferably provided withV a' fender in the form of a vertical stanchion 33 extending over the end of the noat adjacenttlie inside of the dock. These fenders areadapted to be engaged by lthe ferry boat guard',J andeach stanchion may be braced as at 34. Y

The operation of the formV of the ,invention lshown in Figures land Zisas follows:

A ferry boat approachingV thexslip will be steered with reasonable accuracy directly into the slip It is well known that a conventional ferry boat slip functions to guide the boatkinto position as it approaches'its landing position in the slip, and the present `device functions in the same manner except that it cushions the force exerted against one side or the other of the slip if the boat does not move ,accuratelythereinto The arrangement of the anchor chains and their piling Yis such as to prevent substantial movement of the slip and they aredisposedto the best advantage to oppose the greatest forces exerted thereagain'st. The anchoring means including the chains l1 at one side of the float oppose movement of the float in the opposite direction. For example, assuming that the boatinlentering the slip first contacts with the left side thereof as viewedfin Figure 1, the right hand chains I1 and their piling will oppose displacement of the float toward the left. The same movement will lbe opposed by the chains I8 and 20 and their associated piling, `All of the, chainsshown in Figure 1 except the chains i9 extend from their points of connection withvthe float away from the shore line and angularly with respect to the dock over a relatively axes of the boat and the slip I3. Therefore half ofthese'chains'willfalways oppose lateral displacement .of the oatwhen theI boat enters .the slip, and `all of them oppose movement of the float toward the shore when the end of the boat engagestheinner end of the float, The chains movement of the oat away from the shore,v

YThe cushioning action provided by a oating rigid dock is obviously advantageous.` This is particularly true in ferry boat slips since ferry boats are not landed as carefully asother boats vas large or larger. Where stationarypiling is employed, a pile will be frequently broken bythe exertion of force thereagainst yabove the water, there being no support for the: pile ybetween the point of contact of thel boat and the earth beneath the water. Such an arrangement does not provide the cushioning action which is present in the structuredescribed, and the 'latter accordingly mini,- mizes damageboth to the float and to the boat.

I have found that difference in water levels due to changes in tide conditions and consequent differences in the degrees of slackness of the chains do not substantially aiect the operation of the construction. ,In Figure 2 the oat and -several of the chains. have been shownin solid lines as being taut, which is the condition approximately present at ood tide- It will be clear, of course, that if the chains are ever taut, it will be at flood tide, although tautness even at oodtide is not necessary or even desirable The float and the chains have been shown in dotted lines in the approximate positions that would occupy at ebb tide. Under such conditions there will be substantial slack present in the chains. However, the use of heavy chains provides heavy weights acting downwardly to tend to maintain the minimum horizontal distance between the ends of each chain, the weights of the chains thus opposing any displacement of the dock. In other words, the weights of -the chains acting vertically causes resultant forces at the ends of the chains to tend to pull the piles and the dockV toward each other, These resultant forces are balanced on opposite sides due to the uniform angles of divergence from the vertical of the oppositely arranged and oppositely acting chains. The downwardly acting weights of the chains thus tends to center the dock in its proper position while at the same time providing for limited movement of the dock under the impact of a boat landing in the dock olf center, The opposing of the horizontal displacement of the dock is, in effect, a cushioning action, as statedy thus preventing d-amage either to the boat or the dock. To be properly effective in providing the centering and cushioning action, the chains should be always sufficiently slack, whereby the downwardly acting weights of the chains will transmit the proper resultant forces to the piles and to the float. Therefore, at least a reasonable degree of slack in the chains is the normal condition, the chains preferably never being perfectly taut unless the dock is displaced to the limit ofthe slackness of one or more of the chains. Where there are extreme differences in water levels between ebb and flood tides, longer chains may be employed, if necessary, with the respective piling arranged further from the noat, in which case a given downward movement of the dock'will result in a minimum slacking of the chains at ebb tide.

In. the form of the invention shown in Figures 6 an'd 7 a number of individual floats are employed instead of the unitary float structure in Figures 1 and 2;Y These floats are individually connected to thepiling and are adapted topartake of limitedmovementrelative to each other. 'The chains `of the floats are preferably disposed as previously describedto afford the maximum holding effect to minimize displacement of the floats upon the exertion of-forces thereagainst as the boat enters the slipl Where individual relatively small oats are employed they are disposed in any desired manner relative to each other. in accordance with the use to which the dock `is to be put. For example, the floats may be arranged as inv Figure 6 to define a ferry boat slip, and 'each is preferably provided at its inner yend with one of thelfender stanchions to mini'- mize damage tothe relatively light floats, or to provide means projecting above the float a sufficient distance to be engaged by the guard rail of the boat.

It will be apparent that the invention maybe designed for use with any type of boat landing. For example, along straight float may extend transversely of the shore line to act as an ordinary wharf; spaced parallel floats may be ernployed onv opposite sides of such wharf to define slips to receive pleasure or fishing boats, etc.

VIn actual practice it has been found that the piling when completely buried in the groundfrequires aforce of approximately eighty tons to dislodge one of the piles when the dislodging force acts vertically. Obviously, the force required 'to dislodge a pile progressively increases as the force is applied at progressively increasing angles to the vertical. By using angularly arranged flexible members or chains, therefore, forces are applied to the piling under such conditions as to make it practically impossible to dislodge the piling. At the same time this arrangement functions tc maintain a float or dock relatively accurately in position regardless of variations in water levels, particularly where heavy chains are em-I ployed. The present invention compares favorably in its cost of installation to installations of conventional piling, especially with respect to ferry boat slips, since fewer piles are employed. Moreover, the installation once having been made may be considered to be permanent, as distinguished from conventional piling. The use of the invention is therefore far more satisfactory and costs materially less over long periods of time since there is no deterioration or destruction of the piles buried in the ground beneath the water.

It is to be understood that the forms of the invention herewith shown and described are to be taken as preferred examples of the same and that various changes in the shape, size and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the subjoined claims.

I claim:

1. A dock construction comprising a floating dock unit, a plurality of anchoring elements completely embedded in the ground beneath the water, and normally slack flexible elements connecting said dock unit to said anchoring elements at points spaced from the top surface of such ground. said flexible elements being connected to the dock unit at oppositely facing points and diverging downwardly at substantially uniform angles to the vertical.

'3.A dock construction' comprising a dock unit, a plurality of anchoring elements completely. embedded in the ground beneath the water; and normally 'slack relatively heavy chains connectingsaid dock unit to said anchoring elements at points spaced from the top surface of Y suchground,V said relatively heavy chains being connected to the dock unit at oppositely facing points and diverging downwardly at sustantially uniform angles to the vertical. Y i 1 floating dock unit, vertical anchoring elements driven into the Kearth beneath the water and having their upper endsY terminating beneath the surface of the earth, vand 'normally slack relatively heavy `chains"connected at their upper ends to said dock -unit at oppositely facing points thereon, said chains divergingV downwardly at substantially luniform angles to the vertical and being connected at their lower ends tosaid anchoring elements beneathsaid surface ofthe earth.

"745A dock construction comprising a plurality of Viioatscooperating to'form a dock of predetermined shape, a plurality of anchoring elements completely'iembedded in the earth beneath the water, "and at least two normally slack Yflexible elements/connectedrto each float at oppositely facing portions thereof and diverging downwardly at `substantiallyuniform angles to the vertical, each exible -element having its lower end connected tonner `said vanchoring elements below the surface of the earth.

- 5. A dock construction comprising a plurality of oats cooperatingto form a dock of predetermined shape, a. plurality of anchoring elements completely embedded in the earth |beneatl'i the watenrand at least two normally slack exible elements connected to each float' at. opposltely facing portions thereof and diverging downwardly at; substantially uniform angles to the vertical, each'of said flexible elements being in the form of a relatively heavy chain having its lower end connected to one of said anchor' elements at a point spaced below the surface of the earth.

6; A dock construction comprising a plurality of 4floats cooperating to form a dock of predetermined shape, Va plurality of anchoring elements 4elements below the surface of the earth.

'7. A dock construction comprising a plurality 0f floats cooperating to-form a dock of predetermined shape, a plurality of anchoring elements in the form of piles driven into the earth beneath the water and having their upper ends terminating beneath the surface of the earth, and a pair of normally Vslack relatively heavy chains vconnected to each end portion of each float, the pairs of chains of each float diverging downwardlyl at substantially uniform angles to the vertical and each having itslower end secured to one of said anchoring elements at a point spaced below'the surface of the earth,

Y O. FOSS.

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