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EP 0 249 654 B1 |
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EUROPEAN PATENT SPECIFICATION |
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Mention of the grant of the patent: |
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21.02.1990 Bulletin 1990/08 |
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Date of filing: 09.10.1986 |
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International Patent Classification (IPC)5: E02D 17/08 |
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Shore strut assembly for supporting sheathing wall
Verbauvorrichtung zum Abstützen einer Auskleidungswand
Dispositif de soutènement pour le support d'une paroi de blindage
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Designated Contracting States: |
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DE FR GB IT |
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Priority: |
20.06.1986 JP 142651/86
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Date of publication of application: |
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23.12.1987 Bulletin 1987/52 |
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Proprietor: Yugen Kaisha Marukyo Komusho |
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Hirata-shi
Shimane-ken (JP) |
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Inventor: |
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- Uchida, Kyozo
Matsue-shi
Shimane-ken (JP)
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Representative: Patentanwälte
Hauck, Graalfs, Wehnert,
Döring, Siemons |
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Mozartstrasse 23 80336 München 80336 München (DE) |
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References cited: :
DE-A- 3 312 603 US-A- 2 539 703
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DE-B- 1 251 242
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Note: Within nine months from the publication of the mention of the grant of the European
patent, any person may give notice to the European Patent Office of opposition to
the European patent
granted. Notice of opposition shall be filed in a written reasoned statement. It shall
not be deemed to
have been filed until the opposition fee has been paid. (Art. 99(1) European Patent
Convention).
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BACKGROUND OF THE INVENTION:
Field of the Invention:
[0001] This invention relates to a shore strut assembly for supporting a sheathing wall
and more particularly to a shore strut assembly for supporting a sheathing wall that
can be assembled and disassembled easily.
Related Art Statement:
[0002] In the construction of various construction works such as buildings, roads, railroads,
water ducts or dams, soil and sand or rock are first excavated to form a pit within
which various construction works are carried out. For such excavation, a sheathing
wall is formed to prevent the surrounding soil and sand or rock from collapsing.
[0003] Referring to Fig.1, for the formation of a sheathing wall 10, a plurality of sheet
piles 11 are driven to predetermined depth into the ground in neighboring relation
to one another. Then, after digging each sheet pile 11 into the ground to the extent
that the sheet piles 11 are not tilted under the soil pressure, wales 12 for supporting
the sheet piles 11 are attached to the sheet piles in a direction substantially at
right angles with the driving direction of the sheet piles 11. Then, in order to prevent
the sheet piles from tilting towards a pit 13 under the soil pressure, a shore strut
14 is installed between a pair of opposing wales 12, 12 mounted to the sheet piles
11 constituting opposing sheating wall sections 10, 10. In order to adjust the length
of the shore strut to the distance between the wales 12, 12, a jack 15 is attached
to the shore strut 14 so that the shore strut 14 will be correctly mounted in position
between the wales by the extension and retraction of the jack 15. It is noted that
the jack 15 may be mounted between the wale 12 and the shore strut 14 or between the
opposing shore struts 14, 14.
[0004] However, since the jack 15 is extended by manually turning a handle 15a, the manual
force of operations is sometimes insufficient to properly secure the shore strut 14
between the wales 12, 12 so that the shore strut 14 are likely to drop under small
impact. Moreover, the shaft of the jack 15 is apt to be broken in case of elevated
soil pressure. In addition, when the handle 15a is turned manually after the end of
the predetermined construction operations and is gradually retracted the jack 15 for
detaching the shore strut 14, it frequently occurs that the sheet piles 11 are inclined
towards the pit 13 under the soil pressure such that the jack 15 is pinched between
the wale 12 and the shore strut 14 or between the opposing shore struts so that it
becomes impossible to detach the shore struts 14. In this case, it becomes necessary
to dismount the jack 15 by striking it with a hammer or the like with considerable
labor, while the expensive jack may be occasionally destroyed.
OBJECTS AND SUMMARY OF THE INVENTION:
[0005] It is a principal object of the present invention to provide a shore strut assembly
for supporting a sheathing wall which allows the shore strut to be positively secured
without the risk of incidental dropping and without requiring manual operation.
[0006] It is another object of the present invention to provide a shore strut assembly for
supporting a sheathing wall which can be extremely easily assembled and disassembled.
[0007] It is a further object of the present invention to provide a shore strut assembly
for supporting a sheathing wall which allows the shore strut to be instantly disassembled
and dismounted under the prevailing soil pressure.
[0008] It is a further object of the present invention to provide a sturdy and inexpensive
shore strut assembly for supporting the sheathing wall.
[0009] These and other objects of the invention will become clear from the following description.
[0010] According to the present invention, there is provided a shore strut assembly for
supporting an excavation sheathing wall comprising a plurality of blocks each connected
in series to form a parallelepiped as a whole, at least one of the blocks being fastened
to one end of a shore strut for forming an extension of the shore strut and for receiving
pressure acting on the sheathing wall together with the shore strut, at least one
end face of one said block abutting against at least one end face of the adjacent
said block at an angle inclined relative to a plane normal to a longitudinal axis
of the shore strut and the strut assembly so that when disassembling the shore strut
assembly after use, the one block can slide relative to the adjacent block along the
in- dined abutting surfaces by the action of the pressure along the longitudinal axis
of the shore strut and the shore strut assembly so as to be disengaged from the adjacent
block.
BRIEF DESCRIPTION OF THE DRAWINGS:
[0011]
Fig.1 is a perspective view wherein conventional members for supporting the sheathing
wall and the site of excavation are schematically shown.
Fig.2 is a perspective view showing an embodiment of a shore strut assembly according
to the present invention, and showing the assembly when mounted in position.
Figs.3a, 3b and 3c are perspective views showing blocks that make up the shore strut
assembly shown in Fig.2, these blocks being shown so that the inner parts can be seen
through from outside;
Fig.4 is a diagrammatic sectional view taken along line IV - IV of Fig.2.
Fig.5 is a side elevational view showing the shore strut assembly of Fig.2 when mounted
between two shore struts;
Fig.6 is a sectional view showing a further embodiment of the shore strut assembly
of the present invention; and
Fig.7 is a side elevational view showing a further embodiment of the shore strut assembly
of the present invention.
PREFERRED EMBODIMENTS OF THE INVENTION:
[0012] Referring to Figs. 2 to 4, an embodiment of the shore strut assembly of the present
invention is indicated generally by reference numeral 20. In these figures, the parts
or components same as those shown in Fig.1 are indicated by the same numerals. The
shore strut assembly 20 is made up of three blocks 21, 22 and 23 connected together
in series. In the present embodiment, the blocks 21 to 23 are connected together by
bolts/nuts 24. In the actual construction, one or more shore struts 14 of a predetermined
length, H steel beams in the present example, are selected as a function of the size
of the pit 13, while the blocks 21 to 23 are selected from among a number of prefabricated
blocks of various sizes so that these blocks when connected together in position will
approximately fill the gap between the wale 12 and an end plate 14a welded to the
end of the shore strut 14. The end plate 14a and the blocks 21 to 23 may be previously
connected together at the plant and transported to the site of construction for connecting
the block 23 to the wale 12. As an alternative, the block 21 may be previously connected
at the plant to the end plate 14a of the shore strut 14 by bolts/nuts 24, similarly
at the plant and the block 23 connected to the wale 12 at the site of construction.
The block 22 is finally introduced at the construction site between the blocks 21
and 23 and connected by bolts/nuts 24. These bolts/nuts 24 are preferably employed
for connecting the blocks, the end plate and the wale. A bolt tightener, not shown,
may be used for tightening the bolts in situ. The bolt tightener is provided with
an end part for receiving the bolt and being rotated for tightening the bolt. As shown
in Fig.2, the shore strut assembly 20 is securely connected in position between the
shore strut 14 and the wale 12 so that there is no risk of accidental dropping of
the assembly 20.
[0013] In Figs. 3a to 3c, the blocks 21 to 23 are shown in perspective so that the inner
parts thereof can be seen through from outside. The block 21 is a hollow block formed
by an upper plate 21 a, a lower plate 21 b, a vertically extending lateral plate 21
having unnumbered through-holes for passage of tightening bolts, an inclined lateral
plate 21 d having unnumbered through-holes for passage of tightening bolts, and an
inner reinforcement plate 21 e. The block 22 is identically constructed as the block
21 except that the vertically extending lateral plate 21c of the block 21 is replaced
by an inclined lateral plate 22c so that the block 22 has two inclined lateral plates
22c, 22d. Thus, the same reference numerals are used and the description of the other
components of the block 22 is omitted. The block 23 is also identically constructed
as the block 21 except that the blocks are symmetrical relative to each other so that
the block 23 is indicated by the same reference numerals as the block 21 and the redundant
description is similarly omitted.
[0014] As can be seen from Figs. 2 to 4, the blocks 21, 22 and 23 when connected together
in series will form a parallelepiped as a whole, in the present embodiment, a right-angled
parallelepiped, as the extension of the shore strut 14. As shown in Fig.4, the shore
strut assembly 20 and the strut 14 are acted upon by pressure from the sheathing wall
10 along the longitudinal axis x in order to prevent the sheet pile 11 from becoming
tilted in the direction of the pit 13. The inclined lateral plate 21d of the block
21 and the inclined lateral plate 22c of the block 22 abut to each other at an angle
inclined relative to a plane y normal to the longitudinal axis x of the shore strut
14 and the shore strut assembly 20, while the inclined lateral plate 22d of the block
22 and the inclined lateral plate 23c of the block 23 abut to each other at an angle
inclined relative to a plane z normal to the axis x. As will be clarified hereafter,
it is critical in the present invention that the adjacent blocks abut to each other
at an angle inclined relative to a plane normal to the longitudinal axis of the shore
strut and the shore strut assembly.
[0015] After the predetermined operation in the pit 13 is terminated so that it becomes
necessary to dismount the sheathing wall 10, a wire rope, not shown, is attached to
the shore strut 14 in order to hoist the shore strut 14 by a crane, not shown, so
that the shore strut 14 will not drop by gravity during dismounting. The shore strut
assembly 20 is then disassembled. At this time, as shown in Fig.2, the blocks 21,
22 are spot welded to each other along a seamline as at 25, while the blocks 22, 23
are also spot welded to each other along a seamline as at 26 in order to prevent the
soil pressure from being applied to the bolts/nuts 24 while also preventing the block
22 from dropping by gravity during dismounting of the assembly 20. The bolts/nuts
24 connecting the blocks 21, 22 to each other and the bolts/nuts 24 connecting the
blocks 22, 23 to each other are then loosened, after which the upper surface of the
block 22 is struck as with a hammer, not shown, for dismounting. Since the pressure
acts on the inclined lateral plates 22c, 22d of the block 22 in a direction along
the longitudinal axis x of the shore strut 14 and the shore strut assembly 20, as
shown in Fig.4, the block 22 is slid under the operation of the pressure in accordance
with the inclined angle such that the block 22 is instantly disengaged from the blocks
21, 23. The blocks 21, 22 may be loosely connected by a rope 27, for example, in order
to prevent the block 22 from dropping down.
[0016] In case the pit 13 is of a larger widthwise dimension, the shore strut assembly 20
formed by the blocks 21, 22 and 23 may be connected between two shore struts 14, 14,
as shown in Fig.5.
[0017] Fig.6 shows a shore strut assembly 60 which is modified from the shore strut assembly
20 shown in Figs. 2 to 5. The assembly 20 is made up of two blocks 61, 62. The block
61 is formed by an upper plate 61 a, a lower plate 61 b, an inclined lateral plate
61c, a vertically extending lateral plate 61 d and a central inner reinforcement plate
61 e, as in the case of the shore strut assembly 20 of Fig.3. The inclined lateral
plate 61 c is made up of two inclined sections 61 c1, 61 c2 and a step or shoulder
61 c3 interconnecting the inclined sections 61 c1 and 61 c2 with an offset along the
longitudinal axis of the shore strut 14. The block 61 is secured to the wale 12 by
bolts/nuts 24. The block 62 is connected to the shore strut 14 in a topsy-turvied
relation to the block 61 and identically constructed as the block 61 so that redundant
description is omitted for simplicity.
[0018] When mounting the shore strut assembly 60 in position, the shore strut 14 is set
so that the step or shoulder 62c3 of the block 62 rests on the step or shoulder 61c3
of the block 61 as shown. A shim plate 63 is then driven into a space between the
soil and the sheathing wall 10 for tilting the sheet pile 11 so as to abut the blocks
61, 62 to each other. Finally, the blocks 61, 62 are secured to one another by bolting.
The shore strut assembly 60 is convenient when performing a fine adjustment of the
mounting distance. The dismounting of the shore strut assembly 60 shown in Fig.6 is
performed by the same sequence of operations as described with reference to Fig.2.
In this case, the inclined lateral plate 61 of the block 61 is shifted relative to
the inclined lateral plate 62c of the block 62, with the block 62 sliding in the direction
of the arrow mark d.
[0019] Fig.7 shows a further different shore strut assembly 70 consisting of a combination
of the blocks 61, 62 shown in Fig.6. Referring to Fig.7, a left side block 62 is connected
to the shore strut 14, a right side block 62 is connected to the wale 12, and intermediate
blocks 61, 61 are connected between the blocks 61, 61 with vertically extending lateral
plates 61d, 61 d thereof in abutting relation to each other. Fine adjustment of the
mounting distance can be performed by the shim plate 63 and by taking advantage of
the steps 61c3, 62c3. When dismounting the shore strut assembly 70, the blocks 61,
61 can be detached as one from the blocks 62, 62.
1. A shore strut assembly (20, 60, 70) for supporting an excavation sheathing wall
(10) and comprising a shore strut (14), characterised by a plurality of blocks (21,
22, 23, 61, 62) each connected in series to form a parallelepiped as a whole, at least
one (21, 62) of said blocks being fastened to one end of said shore strut (14) for
forming an extension of said shore strut and for receiving pressure acting on said
sheathing wall (10) together with said shore strut (14), at least one end face (21d,
62c) of one said block (21, 62) abutting against at least one end face (22c, 61 c)
of the adjacent said block (22, 61) at an angle inclined relative to a plane (y) normal
to a longitudinal axis (x) of said shore strut and said shore strut assembly so that
when disassembling the shore strut assembly (20, 60, 70) after use, said one block
(21, 62) can slide relative to said adjacent block (22, 61) along the inclined abutting
surfaces by the action of said pressure along the longitudinal axis of said shore
strut and the shore strut assembly so as to be disengaged from said adjacent block
(22,61).
2. A shore strut assembly as claimed in claim 1 wherein end faces (23c, 62c) of other
blocks (23, 62) abut on the other end faces (22d, 61c) of said adjacent blocks (22,
61) at an angle inclined relative to a plane (z) normal to the longitudinal axis (x).
3. A shore strut assembly as claimed in claim 2 wherein said adjacent blocks (22,
61) include two in- dined lateral plates (22c, 22d, 61c) each having a horizontal
dimension increasing towards the lower side to permit the assembly (20, 70) to drop
by gravity upon disassembling thereof.
4. A shore strut assembly as claimed in claim 1 wherein the inclined lateral plate
(62c) of said one block (62) has inclined sections (62c1, 62c2) and a first shoulder
(62c3) interconnecting the inclined sections (62c1, 62c2) with an offset along the
longitudinal axis of the shore strut, and the inclined lateral plate (61 c) of said
adjacent block (61) has inclined sections (61 c1, 61 c2) and a second shoulder (61
c3) interconnecting the inclined sections (61c1, 61c2) with an offset along the longitudinal
axis of the shore strut, and wherein, for assembling the shore strut assembly (60,
70), said one block (62) and said adjacent block (61) are abutted to each other after
said first and second shoulders (62c3, 61 c3) are rested one upon the other.
5. A shore strut assembly as claimed in claim 1 wherein said shore strut assembly
(20, 60, 70) is mounted between the shore strut (14) and a wale (12) supporting said
sheating wall (10).
6. A shore strut assembly as claimed in claim 1 wherein the shore strut assembly (20,
60, 70) is mounted between two shore struts (14, 14).
7. A shore strut assembly as claimed in claim 1 wherein the one block (21, 62) and
the adjacent block (22, 61) are connected together by bolts/nuts (24) passed through
through-holes.
8. A shore strut assembly as claimed in claim 1 wherein each block (21, 22, 23, 61,
62) is hollow and formed by an upper plate (21 a, 22a, 23a, 61 a), a lower plate (21
b, 22b, 23b, 61 b) and two confronting lateral plates (21 c, 21 d, 22c, 22d, 23c,
23d, 61 c, 61 d) interconnecting the upper and lower plates.
9. A shore strut assembly as claimed in claim 8 wherein a reinforcement plate (21
e, 22e, 23e, 61 e) is provided in the hollow block.
10. A shore strut assembly as claimed in claim 1 wherein said one block (21, 62) and
said adjacent block (22, 61) are connected by a connecting member (27) so that the
blocks are not allowed to drop during disassembling of the shore strut assembly.
1. Aussteifung (20, 60, 70) mit einer Strebe (14) zum Abstützen der Schalwand (10)
in einer Baugrube, gekennzeichnet durch mehrere Blöcke (21, 22, 23, 61, 62), die in
Reihe verbunden sind und zusammen ein Parallelepipedon bilden, wobei wenigstens einer
(21, 62) der Blöcke an einem Ende der Strebe (14) als Verlängerung der Strebe befestigt
ist und den auf die Schalwand (10) zusammen mit der Strebe (14) wirkenden Druck aufnimmt,
wobei wenigstens eine Stirnseite (21d, 62c) eines Blockes (21, 62) an wenigstens einer
Stirnseite (22c, 61c) des benachbarten Blockes (62, 61) unter einem gegenüber der
Längsachse (x) der Strebe (y) geneigten Winkel anliegt, so daß beim Zerlegen der Aussteifung
(20, 60, 70) nach dem Gebrauch der Block (21, 62) gegenüber dem benachbarten Block
(22, 61) längs der geneigten Anlageflächen aufgrund des entlang der Längsachse der
Strebe und der Aussteifung wirkenden Druckes gleiten kann und damit von dem benachbarten
Block (22, 61) lösbar ist.
2. Aussteifung nach Anspruch 1, wobei die Stirnseiten (23c, 62c) anderer Blöcke (23,
62) an den anderen Stirnseiten (22d, 61c) benachbarter Blöcke (22, 61) unter einem
gegenüber einer zur Längsachse (x) senkrechten Ebene (z) geneigten Winkel anliegen.
3. Aussteifung nach Anspruch 2, wobei die benachbarten Blöcke (22, 61) zwei geneigte
Seitenplatten (22c, 22d, 61c) aufweisen, von denen jeder eine waagerechte Abmessung
hat, die zur unteren Seite hin größer wird, um beim Zerlegen der Aussteifung (20,
70) diese durch Schwerkraft zu Fall zu bringen.
4. Aussteifung nach Anspruch 1, wobei die geneigte Seitenplatte (62c) des Blockes
(62) geneigte Abschnitte (62c1, 62c2) und eine erste Schulter (62c3) aufweist, welche
die geneigten Abschnitte (62c1, 62c2) in der Längsachse der Strebe versetzt miteinander
verbindet und wobei die geneigte Seitenplatte (61c) des benachbarten Blockes (61)
geneigte Abschnitte (61c1, 61 c2) und eine zweite Schulter (61c3) aufweist, welche
die geneigten Abschnitte (61c1, 61 c2) in der Längsachse der Strebe versetzt miteinander
verbindet, und wobei beim Zusammenbau der Aussteifung (60, 70) der Block (62) und
der benachbarte Block (61) aneinander gestoßen werden, nachdem die erste und zweite
Schulter (62c3, 61 c3) aufeinander gelegt worden sind.
5. Aussteifung nach Anspruch 1, wobei die Aussteifung (20, 60, 70) zwischen der Strebe
(14) und einer die Schalwand (10) abstützenden Bohle (12) angeordnet ist.
6. Aussteifung nach Anspruch 1, wobei die Aussteifung (20, 60, 70) zwischen zwei Streben
(14, 14) angeordnet ist.
7. Aussteifung nach Anspruch 1, wobei der Block (21, 62) und der benachbarte Block
(22, 61) mit Schrauben/Mutterverbindungen (24) in Durchgangsbohrungen miteinander
verbunden sind.
8. Aussteifung nach Anspruch 1, wobei jeder Block (21, 22, 23, 61, 62) hohl ist und
aus einer oberen Platte (21a, 22a, 23a, 61a), einer unteren Platte (21 b, 22b, 23b,
61 b) und zwei gegenüberliegenden Seitenplatten (21 c, 21 d, 22c, 22d, 23c, 23d, 61
c, 61 d) besteht, welche die oberen und unteren Platten miteinander verbinden.
9. Aussteifung nach Anspruch 8, wobei eine Verstärkungsplatte (21e, 22e, 23e, 61e)
in dem hohlen Block vorgesehen ist.
10. Aussteifung nach Anspruch 1, wobei der Block (21, 62) und der benachbarte Block
(22, 61) mit einem Verbindungsglied (27) verbunden sind, so daß die Blöcke während
des Zerlegens der Aussteifung nicht herunterfallen können.
1. Ensemble d'étrésillonnage (20, 60, 70) destiné à étayer la paroi de blindage (10)
d'une fouille qui comprend un étrésillon (14), caractérisé en ce qu'il comprend une
pluralité de blocs (21, 22, 23, 61, 62) qui sont tous reliés en série pour former
ensemble un parallélépipède, au moins l'un (21, 62) desdits blocs étant fixé à une
extrémité dudit étrésillon (14) pour former un prolongement de l'étrésillon et pour
recevoir, en même temps que l'étrésillon, la pression qui agit sur la paroi de blindage
(10), au moins une face terminale (21 a, 62c) dudit premier bloc (21, 62) s'appuyant
contre au moins une face terminale dudit bloc adjacent (22, 61) selon une direction
inclinée par rapport au plan (y) normal à l'axe longitudinal (x) dudit étrésillon
et dudit ensemble d'étrésillonnage de telle manière que, lorsqu'on désassemble l'ensemble
d'étrésillonnage (20, 60, 70) après utilisation, le premier bloc (21, 62) glisse par
rapport au bloc adjacent le long des surfaces d'appui inclinées sous l'effet de la
pression qui s'exerce selon l'axe longitudinal de l'étrésillon et de l'ensemble d'étrésillonnage,
de manière à se dégager ainsi du bloc adjacent.
2. Ensemble d'étrésillonnage selon la revendication 1, dans lequel les faces terminales
(23c, 62c) d'autres blocs (23, 62) s'appuient contre les autres faces terminales (22d,
61c) desdits blocs adjacents (22, 61) selon une direction inclinée par rapport à un
plan (z) normal à l'axe longitudinal (x).
3. Ensemble d'étrésillonnage selon la revendication 2, dans lequel lesdits blocs adjacents
(22, 61) comprennent deux plaques latérales inclinées (22c, 22d, 61 c), chacun possédant
une dimension horizontale qui croît vers le côté inférieur pour permettre à l'ensemble
(20, 70) de tomber par gravité lorsqu'on le désassemble.
4. Ensemble d'étrésillonnage selon la revendication 1, dans lequel la plaque latérale
inclinée (62c) dudit premier bloc (62) possède des sections inclinées (62c1, 62c2)
et un premier épaulement (62c3) qui assemble les sections inclinées (62c1, 62c2) avec
un décalage dans le sens de l'axe longitudinal de l'étrésillon, et la plaque latérale
inclinée (61c) dudit bloc adjacent (61) possède des sections inclinées (61 c1 , 61
c2) et un deuxième épaulement (61 c3) qui relie les sections inclinées (61c1, 61 c2)
avec un décalage dans le sens de l'axe longitudinal de l'étrésillon, et dans lequel,
pour assembler l'ensemble d'étré- sillonnage (60, 70), on met ledit premier bloc (62)
et ledit bloc adjacent (61) en appui l'un contre l'autre après avoir fait reposer
lesdits premier et deuxième épaulements (62c3, 61c3) l'un sur l'autre.
5. Ensemble d'étrésillonnage selon la revendication 1, dans lequel ledit ensemble
d'étrésillonnage (20, 60, 70) est monté entre l'étrésillon (14) et une longrine (12)
qui soutient la paroi de blindage (10).
6. Ensemble d'étrésillonnage selon la revendication 1, dans lequel l'ensemble d'étrésillonnage
(20, 60, 70) est monté entre deux étrésillons (14, 14).
7. Ensemble d'étrésillonnage selon la revendication 1, dans lequel premier bloc (21,
62) et le bloc adjacent (22, 61) sont assemblés l'un à l'autre par des boulons (24)
enfilés à travers des trous traversants.
8. Ensemble d'étrésillonnage selon la revendication 1, dans lequel chaque bloc (21,
22, 23, 61, 62) est creux et formé d'une plaque supérieure (21 a, 22a, 23a, 61a),
d'une plaque inférieure (21b, 22b, 23b, 61b) et de deux plaques latérales opposées
(21c, 21 d, 22c, 22d, 23c, 23d, 61c, 61 d) qui relient les plaques supérieure et inférieure.
9. Ensemble d'étrésillonnage selon la revendication 8, dans lequel une plaque de renforcement
(21 e, 22e, 23e, 61 e) est prévue dans le bloc creux.
10. Ensemble d'étrésillonnage selon la revendication 1, dans lequel ledit premier
bloc (21, 62) et ledit bloc adjacent (22, 61) sont assemblés par un élément d'assemblage
(27) de telle manière que les blocs ne puissent pas tomber pendant le désassemblage
de l'ensemble d'étrésillonnage.