US2863291A

US2863291A - Reinforced dam

Info

Publication number: US2863291A
Application number: US415127A
Authority: US
Inventors: Murmann Wilhelm
Original assignee: Hochtief AG
Current assignee: Hochtief AG
Priority date: 1953-03-11
Filing date: 1954-03-09
Publication date: 1958-12-09
Anticipated expiration: 1975-12-09

Description

W. MU RMANN REINFORCED DAM Dec. 9, 1958 Filed March 9. 1954 WILHELm MURMAHUI REINFORCED DAM Wilhelm Murmann, Kleve, Lower Rhine, Germany, as

signer to Firma Hochtief Alrtiengesellschaft fiir Hothund Tiefbanten, vorrn. Gehr. Helfmann, Essen (Ruhr), Germany Application March 9, 1954, Serial No. 415,127 Claims priority, application Germany March 11, 1953 7 Claims. (Cl. 61--31) The present invention relates to a structure for reinforcing a dam, and more particularly to a wall structure for reinforcing the top portion of a darn consisting of earth and rubble stones.

Dams of this type serve as dykes and barrages across valleys and are consequently exposed to substantial water pressure on one side.

In the event that water flows even over a portion of the crown of a dam consisting of earth 'and rubble stones, the material of the dam is gradually washed away so that any opening is rapidly widened and the dam is soon destroyed. It has been found that a bomb explosion causing comparatively small damage to the crown of a dam of this type may lead to the collapse of the entire dam structure.

It is one object of the present invention to provide means preventing formation of an opening permitting passage of Water in a dam crown, even if the dam crown is hit by a bomb.

It is another object of the present invention to provide in a dam a reinforcing structure which can be easily repaired if damaged.

It is a further object of the present invention to reinforce the top portion of a dam consisting of earth and rubble stones by a Wall structure embedded therein and consisting of a plurality of wall elements which are connected to each other for relative movement so as to permit giving of the wall structure under the force of a bomb explosion.

It is yet another object of the present invention to provide on connected reinforcing wall elements, which are embedded in the top portion of a dam, transversely projecting wall portions abutting against the surrounding dam material and preventing separation of the wall elements.

With these objects in view the present invention mainly consists in a dam structure comprising, in combination, an elongated dam body, and an elongated reinforcing structure embeded in the dam body and extending in longitudinal direction of the Same. The reinforcing structure includes a plurality ofwall elements connected to each other for limited relative movement. The wall elements consist preferably of reinforced concrete and are provided with integral transversely projecting reinforced concrete wings which increase the rigidity of the structure and form open cells which are filled with the material of the dam body so that the wall elements are held together and separation in longitudinal direction is prevented. In order to increase the friction between the wall structure and the earth surrounding the same, preferably projecting ledges and recesses are provided, which may be produced by using corrugated molds during the pouring of the concrete. In order to better anchor the structure in the surrounding material, the bottom edges of the wall elements and of the projecting wall portions are preferably provided with projecting ledges.

The adjacent wall elements are connected to each other aired States i atent 2,3632% Patented Dec. 9, 1958 by connecting means which prevent longitudinal separation of the wall elements, but permit a relative angular movement of the same.

It will be apparent that a wall structure of this type will slightly yield under the pressure of a bomb explosion so that the wall elements engage and are supported by the surrounding material of the dam body. Due to the projecting wings the pressure of an explosion will be also distributed in longitudinal direction to the dam body so that the effect of the explosion will cause only localized damage.

Preferably the reinforcing wall structure is arranged in the center of the top portion of the wall so that exploding bombs will be only effective on one side of the wall structure, while the other side of the dam crown will remain intact and prevent overflow of water.

The upper edge of the reinforcing wall is located substantially below the top surface of the dam, but above the highest water level so that even if the uppermost darn portion is destroyed, the dam portion which is reinforced by the wall structure will still be located above water level and prevent overflow.

It will be apparent that such partial damage can be easily and rapidly repaired, while a breakthrough of Water in a normal dam construction will wash out the dam and make emergency repairs impossible.

Preferably, the reinforcing wall structure projects 1 to 2 yards above the water level, and extends downwardly into the dam body for about 10 to 20 yards below the water level. At such distance from the water level the thickness of dams of this type is so great that even a highly effective bomb will be incapable of breaking through the dam.

According to a preferred embodiment of the present invention the weight of the reinforcing structure is distributed onto the dam body by a base member which extends along and underneath the wall structure sup porting the same slightly tiltable in transverse direction.

In dams of this type it is known to provide a concrete passage within the dam body through which the structure may be inspected. The reinforcing wall structure may be supported on such concrete passage to permit the wall structure to transversely tilt to a slightly inclined position in the event of earth movements.

According to another preferred embodiment the bottom edges of the wall elements are flanged and have transversely projecting ledge portions. In this event the base member may be omitted.

It is advantageous to connect the wall elements to each other in such manner as to permit a slight relative movement in vertical direction so as to permit the wall structure to follow the earth movement during setting of the material of the dam body.

Dams having a very thick crown portion are preferably reinforced by two parallel spaced wall structures which are preferably connected by slack tension transmitting means, such as heavy chains.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, in which:

Fig. 1 is a horizontal sectional view on line 1-1 in Fig. 2;

Fig. 2 is a vertical transverse sectional view through a dam structure according to the present invention taken on line 22 in Fig. 1;

Fig. 3 is a horizontal sectional view on line 3---3 in Fig. 2;

Fig. 4 is a fragmentary transverse sectional View of a modified embodiment of the present invention and corresponding to Fig. 2; and

Fig. is a fragmentary transverse sectional view of another embodiment of the present invention and corresponding to Fig. 2.

Referring now to the drawing and more particularly to the embodiment illustrated in Figs. 1, 2 and 3, in a dam body 20, or in the top portion of a dam body 26, a reinforcing structure is symmetrically arranged which consists of a plurality of wall elements 1 arranged in a row extending longitudinally in the dam body. Each of the wall elements has preferably a length of 60 to 90 feet and has a plurality of transversely projecting wall portions or wings 2 projecting from both sides of the wall elements and forming cells 4, the wall portions 2 on each side being staggered with respect to the wall portions 2 on the other side of the respective wall element.

Haunch portions or ledges 3 are provided along the lines at which the wall portions 2 join the main portion of the wall elements 1. The shape of the wall portions 2 is best seen in Fig. 2 which shows the wall portions 2 to be of downwardly reduced width.

Adjacent wall elements are connected to each other in such manner that the adjacent wall elements are free to perform a limited angular movement relative to each other aboutaxes located in the plane of the wall structure, while being locked against separation in longitudinal direction of the dam. In the preferred embodiment illustrated in Figs. 1 to 3, adjacent edges of adjacent wall elements are connected by connecting members which are spaced in vertical direction as shown in Fig. 2. The connecting members 9 consist of reinforced concrete and have two T-shaped heads which are held in corresponding recesses 8 in adjacent wall elements. At least one edge of a pair of adjacent-edges of adjacent wall elements is rounded, as indicated at lla, or adjacent edges are spaced so that adjacent wall elements 1 may assume an angularly displaced position, which is possible since sufficient play is provided for the members 9 in the recesses 8. The members 9 have also some play in vertical direction so that a slight relative shifting of the wall elements 1 in vertical direction is possible in the event that portions of the dam body set to adiflerent extent; The concrete of the Wall structure is poured in horizontal layers, so that the recesses 3 in each layer are first provided, whereupon the respective connecting members 9 are placed in the recesses. The next horizontal layer of concrete is then poured so that the connecting members 9 are completely enclosed in recesses 8.

Adjacent edges of adjacent wall elements 1 are provided intermediate the connecting members 9 with tongue and groove means 6, 7 as best seen in Fig. 3. The tongue and groove connection permits relative vertical and angular movement of adjacent Wall elements, but is incapable of holding and locking the wall elements to gether to prevent separation in longitudinal direction, for which purpose the connecting members 9 are provided. It will be apparent that wall elements 1 connected by a connecting means 6, 7, 8, 9 are capable of relative angular movement to a limited extent, but are locked against separation in longitudinal direction.

A base plate '10 supports the bottom edge 14 of the wall structure which is preferably slightly arcuate so as to permit the wall elements 1 to assume a slightly tilted position which is made possible also by the cut-out 11 in the main portion of each wall element l.

in the event that the dam body is not very high, the reinforcing wall structure extends to the base of the darn, while it will be sulficient to reinforce only the top portion of a higher dam.

Fig. 4 illustrates an embodiment in which at the bottom of a low dam a concrete passage 13 is provided which serves for inspection of the dam structure. Such passage 4 is used in the embodiment of Fig. 4 for supporting the wall elements 1.

Fig. 4 illustrates an embodiment in which the projecting wall members 2a have an almost rectangular shape, and are reinforced along their bottom edges by projecting ledges 12 which improve the anchorage of the wall structure in the material of the dam.

in Fig. 5 a modified embodiment is illustrated according to which the wall elements 1" are inclined toward the downstream side of the dam. The projecting wall portions are unsymmetrical and the lower wall portion is provided along its bottom edge with a reinforcing ledge 12 which serves for anchoring the wall structure in the material of the dam. in a construction of this type, a supporting base member is unnecessary since the ledges distribute the weight sufficiently on the material of the dam body.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of reinforcing structures for dams differing from the types described above.

While the invention has been illustrated and described as embodied in a wall structure consisting of a row of wall elements embedded in the top portion of a dam and connected to each other for relative angular movement, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be secured by Letters Patent is:

l. A dam structure comprising, in combination, an elongated dam body of loose material; and an elongated reinforcing structure entirely embedded in said dam body spaced from the top thereof and extending in longitudinal direction and only in the upper portion of the same, said reinforcing structure including a plurality of wall elements connected to each other for .relative movement, each of said wall element comprising on each face thereof at least two transversely projecting wings forming together with the wall elements open cells.

2. A darn structure comprising, in combination, an elongated dam body of loose material; and a Wall structure entirely embedded in said dam body extending spaced from the top thereof in longitudinal direction of the same and comprising a row of Wall elements, at least two transversely projecting wings on each side of each wall element integral with the same and forming together with said wall elements open cells, the transversely projecting wings on each side of each wall element being staggered relative to the transversal wall portions on the other side of the respective wall element, and connecting means connecting adjacent Wall elements to each other for relative angular movement about axes located in the plane of said wall structure, said connecting means locking said wall elements to each other to prevent separation of said wall elements in longitudinal direction of said wall structure.

3. A dam structure comprising, in combination, an elongated dam body of loose material; a wall structure entirely embedded in said darn body spaced from the top thereof extending in longitudinal direction of the same and comprising a plurality of wall elements arranged in a row, each of said wall elements having edges engaging adjacent edges of loosely connected adjacent wall elements, each of said wall elements comprising on each face thereof at least two transversely projecting wings forming together with the wall elements open cells, a plurality of tongue and groove means having clearances between the connected means thereof and located spaced from each other along each pair of adjacent edges of each two adjacent wall elements and permitting relative angular movement of adjacent wall elements to a limited extent; and a plurality of connecting members arranged spaced from each other and staggered relative to said tongue and groove means along each pair of adjacent edges of adjacent Wall elements, said connecting members locking adjacent wall elements to each other in longitudinal direction of said wall structure to prevent separation of said wall elements and being so shaped as to permit relative angular movement of adjacent wall elements to a limited extent.

4. A darn structure comprising, in combination, an elongated dam body of loose material; a wall structure entirely embedded in said dam body spaced from the top thereof extending in longitudinal direction of the same and comprising a row of wall elements, each of said wall elements comprising on each face thereof at least two transversely projecting wings forming together with the wall elements open cells, and connecting means connecting adjacent wall elements to each other for relative angular movement about axes located in the plane of said Wall structure, said connecting means locking said wall elements to each other to prevent separation of said wall elements in longitudinal direction of said wall structure; and a base member embedded in said dam body underneath said wall structure and supporting said wall elements.

5. A dam structure as claimed in claim 4 wherein each of said wall elements has a bottom edge having an armate cross section so as to be adapted to support the respective Wall element for a rocking movement on said base member.

6. A dam structure comprising, in combination, an elongated dam body of loose material; a wall structure entirely embedded in said'dam body spaced from the top thereof extending in longitudinal direction of the same and comprising a row of wall elements, each of said wall elements having a bottom edge of arcuate cross section, at least two transversely projecting Wings on each side of each wall element integral with the same and forming together with said Wall elements open cells, the trans versely projecting wall portions on each side of each wall element being staggered relative to the transversal wall portions on the other side of the respective wall element, and connecting means connecting adjacent wall elements to each other for relative angular movement about axes located in the plane of said wall structure, said connecting means locking said Wall elements to each other to prevent separation of said wall elements in longitudinal direction of said wall structure; and a base member embedded in said dam body underneath said Wall structure extending along and supporting the same, said base memher being formed with a longitudinally extending passage and serving for inspection of said wall structure.

7. A dam structure as claimed in claim 2 wherein said wall elements and said projecting wings consist of con crete and are formed with vertical ridges and recesses for frictionally engaging the material of said dam body.

References Cited in the file of this patent UNITED STATES PATENTS 72,913 Schooley Dec. 31, 1867 635,906 Wilson Oct. 31, 1899 923,831 Hall June 8, 1909 1,001,963 Latham Aug. 29, 1911 1,041,035 Cummings Oct. 15, 1912 1,044,992 Collom Nov. 19, 1912 1,578,444 Knight Mar. 30, 1926 1,888,630 Knight Nov. 22, 1932 1,988,777 Bohrisch Jan. 22, 1935 2,387,431 Du Laney Oct. 23, 1945 2,507,259 Levasseur May 9, 1950 FOREIGN PATENTS 875,815 France 1942