US 2609666 A
Description (OCR text may contain errors)
Sept. 9, 1952 J. MESNAGER- 2,609,665
I DAM Filed June 29, 1948 3 Sheets-Sheet 1' INVENTOR: Jacques Mesnager j His Agent Sept. 9, 1952 Y J. MESNAGER 2,609,666
Filed June 29, 1948 3 Sheets-Sheet 2 Fig .9.
INVEN TOR: Jacques Me snag er His Agent J. MESNAGER Sept. 9, 1952 DAM 3 Sheets-Sheet 5 Filed June 29, 1948 INVENTOR. TACQUES MESNAGER Patented Sept. 9, 1952 A UNITED, STATE S PATENT zgcoatcs DAM Jacques Mesnager, Paris, France I Application June 29, 1948, Serial No. 35,7 54 In France July 2, 1947 The pressure or thrust of the water subjects a deformable wall in the vertical plane to either tensional or compressive stresses depending on whether the curved-vertical outline of the wall is intended to resist the hydrostatic pressure with its concave or its convex side, at the same time as the anchorings by which it is secured at its edges are similarly subjected to'either tensional or compressive stresses.
The deformable wall assumes the shape of a catenary curve which is the resultant of the pressures or thrusts of the liquid and of its own weight; this shape is an elastic plane or linear Bernouillis curve, where the weight of the wall is negligible. This curve varies with the level of the liquid ahead of the dam.
The flexible wall is stressed tensionally in the vertical plane and free from any bending stress irrespective of the level of the liquid. It may therefore be constituted by a very thin membrane: a metallic sheet, asphaltor tar-lined (contingently metal) cloth, waterproof cloth, etc. Generally, only the atmospheric air is present on the opposite side of the water-retaining wall. According to a further feature of the invention, this atmospheric air may be replaced by pressure air, or gas, or liquid, which thus becomes effective to support the wall. This is possible where the deformable wall forms a sort of air or water chamber on whose wall the fluid compressed inside of it exerts a pressure that will support the wall. This arrangement allows to install adjustable dams or sluice-gates the height of which is variable in dependency on the pressure of the fluid and on the head.
Depending on whether a compressed fluid is used or not, and on whether the wall is stressed tensionally or compressively, different ways of carrying the invention into effect are possible, of which some are shown byway of example in the accompanying drawings.
Fig. 1 is a diagrammatic vertical sectional view of an embodiment comprising a deformable wall; Figs. 2 and 3 are corresponding views of two modifications of the embodiment shown in Fig. 1; Figs. 4 and 5 show two embodiments of a deformable wall whose upper edge can be wheeled on a rail displaced by means of a float;
Figs. 6 and 7 are-diagrammatic vertical sectional views of two embodiments, in which the deformablewall is stressed compressively;
Fig. 8 is a diagrammatic vertical sectional view of a deformable wall forming a chamber for pressure fluid; I
Figs. 9 to, 13 show various embodiments of-a ribbed, ,a rippled .or-a flanged deformablewall;
Figs.- 14 and 15,are'v iews of two embodiments in which the ,liquid-retainingwall is rigid; 31 Fig'.,16 isa view-ofanembodiment in which the wall can be woundup about a roller; and.
Fig. 1'7 shows one further embodiment ofma damconstructed in accordance with the present invention. 1. V
Inthe caseof the Figure 1, an edge E of the deformable wall P is anchored in they soil S while the. other. edgeF is-proppedr by asupport A which may be movable, for instance by the hinging of its two ends or the wheeling of its-bottom end. This latter type of construction, is shown in Fig. 17 where the. support A in the form of rigid, planar frame, is'connected to edge F,of deformable walllPand fixedly connected: at'A to a platform Z mounted onrollers.
Means may be provided which allow; lowering or raising the edge F so as to, discharge the liquid retained over the same. Y T
A considerable advantage of the constructional rocess according to the invention resides in the fact that the weight G of ahuge mass of liquid retained contributes in ensuring the stability of the support A of the wall P. Effectively, in
order to prevent thepropA-from overturning,
it is necessary that the resultant H of the. pressure' or thrust'I and the weight G should go through the foot of the prop A. With this end in view, the weight G shouldnot be too small, as compared to the'pressure or. thrust;I.; Since the. wall vP: according 'to the invention provides a curved facing, the weight of the liquid retained between the vertical planes of the edges E and F is large enough to ensure the stability ofthe support A and of the wall P, whereas in dams with a vertical or slightly slopinglining, it is.
necessary to use a huge mass of costly material to ensure this stability. The invention therefore cuts down the volume of materials to be used and consequently the costs of erection.
The support A may take different shapes some of which are as follows:
(a) A vertical (Fig. l). or sloping (Fig. 2) propping wall which may be plane or cylindrical depending on whether the dam is straight or arcuate; 1 j
resisted by the anchorage of the wall P in the ground. A chain D prevents the float u from losing its trim.
The movableness of the prop is advantageous in that it enables the movable wall to retain its .nected to a horizontalthin wall (Fig. 6) or anchored in the earth (Fig. 7-).
The deformable wall P which on the his hand undergoes like in the previous cases tensional or compressive stresses in: the vertical plane may on the other hand be subjected to stresses which may be nul;-oriof tensile, or of compressive chara'eter depending on whether the dam is straight orhas its concavity turned downstreams or upa tr'eajms,
. In the embodiment oiFig; S the deformable wall P is subjected on its one side to the pres-- sure of the liquid, andon the other to the variable pressure of 'a-liquid Zcom'pressed'as desired. 1 The two edges of the wall are anchored in the ground or ina massintegral therewith and the wallP forms achamber 'into which a compressed fluid is forced by suitable means. Pipes X and Y are provided through which fluid can be 1 fo'rced'in or let out. According to the'pressure given to this fluid and according to'tlie'level of the liquidrthe .wallwill take a defined. shape."
' If-the pressure ofthe compressed fluid decreases,
the'wall will collapse (position shown by the dotted lines) and the liquid retained can discharge over its top. Visible in Figure 8 are an inspection passage V and a pile-plank curtain or parapet wall W.
The wall P maybe stiifened by horizontal ribs M (Fig. 9) even where it is deformable or according to lines of swiftest descent N (Fig. 10)
where it is indeformable. In this case it may be composed of toric members T which may be "stressed compressively (Fig. ll) or compressively (Fig-12) in the hor'izontaldireetioni' The deformable wall consists of juxtaposed "cylindrical sections B (-FigfillS) interconnected. b'y' cables or tie rods C orrbiy stops the whole -=s'tructure being braced.
. There maybeu'sed, especially where the liquid level varies little, walls suitable stiffened so as to keep their shape irrespective of the liquid level, said shape may here again be a catenary cor-responding tothe pressures of the average level or to the one most frequently assumed by the liquid, or'to 'the one which will give the lowest bending stresses when variation of the level is most unfavorable.
The wall may then be rested on props (Figs. 12 and 14) or on arcatures (Fig. '3), or braced (Figs. 6, 7, l3 and 14) or rested on spandrels by which it will be maintained not only at'its. topbe unequal in diameter.
4 edge but also at points intermediate between its top and its bottom edges.
Where the wall is thus stiffened, concrete (which may or may not be reinforced or prestressed) may advantageously be used as the building material.
Fig. 16 shows a further embodiment in which the flexible wall p is wound around a roller in the one direction while ropes Q retained at their top ends'are wound on the roller R in the reverse direction. The pressure of the liquid retained by the wall tends e. g. to unwind the latter in the direction shown by the arrow in Figure 16 while the pull exerted on the ropes Q tends to rotate the roller R, in the opposite direction. A balancewill thus set in where the roller R and the one on which the flexible wall is wound are equal in diameter. The wall p is thus retained at its top edge. The weight of the rollers must be supported by suitable ropes or cables by means of which the system can be wound in OlUOllt as desired. The rollers for the windingi'of the flexible wall and of the ropes orcables inay'also Racks may be substituted for the cables. The ends of the roller R. are received in grooves J provided in the walls 0' and can bear. on the walls ofsaid grooves. 1., V
What I claim as my invention andnesire .to secure by Letters Patent isr- 1. A dam, comprising, in combinationy a wall made of flexible sheet material and haviiig substantially straight, parallel, and horizontal top and bottom edges extending. across a bodyfiof water in which the dam is located with said bottom edge of said wall fixed to the bed-on which the water is located, and said wall forming part of a cylinder having a horizontal generatri-xsubst-anti'ally parallel to said top and bottom; edges of said wall; and support means conneotedto said top edge or" saidwall to supportsaid top edge formovein'ent while maintaining aid top edge parallel to said cylindergener-atrr i 2. A dam, comprising; in ooinbinati-on,--a wall made of flexible sheet materialand having-substantially straight, parallel, and horizontal top and bottom edges eXten-dingacross ap'bod-y- 'of water in which the dam is'located with said bottom edge of said. wall fixed-to th bedpn which the water is l.ocated,,and sai-d'iW-all-ionning par-t of a cylinder having a ho'rizonal generatrix substantially parallel ,to'said'itcp andbottom edges of said wall; and support means-connected to said top edge oi'said' wall to support said top edge for free movement under theyactionoi the body of water while maintainingsaid top edge parallel to said cylinder generatrix.
3. A darn, comprising, in combination a wall -'made of flexible sheet material and shaving; sub
stantially straight, parallel, and horizontaltop and bottom edges extending across "a'rbody of water in which the darn is located with said brittom edge of said wall fixed to the bed on which the wa ter isloicated, and said wall forming part-of a'cyiinder having a horizontal generamade of flexible sheet material and having substantially straight, parallel, and horizontal top and bottom edges extending across a body of water in which the dam is located with said bottom edge of said wall fixed to the bed on which the water is located, and said wall forming part of a cylinder having a horizontal generatrix substantially parallel to said top and bottom edges of said wall; a float floating on the body of water and being connected to said top edge of said wall to support the same for free movement under the action of the body of water.
5. A dam, comprising, in combination, a wall made of flexible sheet material and having substantially straight, parallel, and horizontal top and bottom edges extending across a body of water in which the dam is located with said bottom edge of said wall fixed to the bed on which the water is located, and said wall forming part of a cylinder having a horizontal generatrix substantially parallel to said top and bottom edges of said wall; and a planar supporting structure extending across and being movably mounted on the bed on which the body of water is located and having an upper edge portion connected to said top edge of said wall to sup- REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 289,959 Bigelow Dec. 11, 1883 536,-687' Hussey Apr. 2, 1895 771,821 Gleazen Oct. 11, 1904 787,525 Meyers Apr. 18, 1905' 800,313 Meyers Sept. 26, 1905 FOREIGN PATENTS Number Country Date 353,366 Norway 1921 35,367 Norway 1921 530,696 France 1921