[0001] The present invention relates to the field of anchorage systems for geotechnical
use, and more specifically relates to an anchorage device for anchorage tie rods and
to a process for anchoring such tie rods.
[0002] In the field of geotechnical engineering, it is known to use anchorage tie rods which
are installed within a perforating hole to stabilize rocky walls, make bearing walls,
partition walls, consolidate excavation walls, tunnels, etc. In particular, there
are various types of tie rods, such as e.g. strand, bar, cable, tube tie rods, etc.
[0003] Anchorage tie rods of the known art broadly consist of three main elements: the anchorage
head, the free length and the active length (the latter also referred to as a restrained
length or foundation bulb).
[0004] The anchorage head typically consists of a steel plate having shape and sizes such
as to allow the transfer of the stresses onto a contrast structure such as e.g. a
reinforced cement wall, partition wall, bearing wall, etc. The free length, which
is the stretch measured from the head of the tie rod up to exceeding the slide line
of the ground, forms the part of the tie rod not restrained to the ground in which
the reinforcement of the tie rod, which generally is protected with a sheath, may
be freely extended.
[0005] The active length is the part of the tie rod in which the reinforcement of the tie
rod is anchored to the ground by means of the injection of the final stretch of the
perforating hole by means of cement mortar. Once the injection of the cement mortar
is complete and it has hardened, the tie rod is tensioned with jacks and hydraulic
power units and the reinforcement is fastened at the head with suitable locking clamps.
Thereby, the active length transfers the load applied to the ground due to the friction
resistance due to the mortar-ground adhesion.
[0006] Therefore, as may be understood, the operating principle of anchorage tie rods commonly
used is based on the resistance to extraction obtained due to the friction between
the injected bulb and the surrounding ground.
[0007] As clarified below, a drawback of the above-described anchorage tie rods of the known
art is due to the fact that often during the useful life of a tie rod or even after
a few hours from the placement thereof at the site, there are losses of adhesion such
as to compromise the resistance of the anchorage, thus jeopardizing the stability
and safety of the work itself.
[0008] Certain considerations have been provided below to better clarify the technical problems
which often occur in anchorage tie rods currently used.
[0009] The injection of the active length of the tie rod is a very delicate and tricky operation
for many types of grounds (grounds with alluvial features, unconsolidated stratifications)
because more often than not, an adequate mortar-ground adhesion cannot be obtained,
an adhesion such as to ensure the resistance to extraction. In many situations, the
injections become necessary also after the tensioning of the tie rod precisely because
often there are losses of adhesion with the ground, while also implementing suitable
additives for mitigating the phenomenon of the cement mortar shrinking.
[0010] It indeed is known that complications may occur such as to significantly impact the
resistance to extraction during the placement and also during the useful life of the
tie rods actually used.
[0011] It is therefore apparent that the greater the active length and perforating diameter
for conventional anchorage tie rods, the greater the hold of the tie rod.
[0012] The active length of a classic anchorage tie rod therefore may vary from a minimum
of 3 to 4 meters up to reaching a length of about 40 meters in certain types of grounds.
[0013] Therefore, the main parameter to be assessed during the design step is precisely
the resistance that the anchoring should put up to the extraction from the ground.
In the calculation, only one estimate may be obtained of such a parameter by means
of analytical and semi-empirical methods, using the results from geological prospecting
and laboratory tests for determining geotechnical parameters of the ground. In any
case, legislation obligates the designer to perform load tests on the tie rods in
order to arrive at an experimental measurement of the value of resistance to extraction.
The calculation of the connected stretch becomes even more problematic in the presence
of unconsolidated, sandy, fractured grounds, or even worse in the presence of subsurface
water, because additional conditions arise which are difficult to schematize with
analytical formulations and in many cases, not even the test tie rods reassure the
designer on the hold of the work.
[0014] It is a general object of the present description to provide an anchorage device
for anchorage tie rods which allows the above drawbacks with reference to the anchorage
tie rods of the known art to be at least partly resolved and obviated.
[0015] These and other objects are achieved by means of an anchorage device for tie rods
as defined in claim 1 in the most general embodiment thereof, and in the dependent
claims in certain particular embodiments thereof.
[0016] An assembly of parts as defined in claim 5 is also the subject of the present invention.
[0017] Moreover, a process for anchoring anchorage tie rods as defined in claim 6, is the
subject of the present invention.
[0018] Moreover, an anchorage device for anchoring anchorage tie rods as defined in claim
7, is the subject of the present invention.
[0019] Moreover, an assembly of parts as defined in claim 14 is the subject of the present
invention.
[0020] Moreover, a process for anchoring anchorage tie rods as defined in claim 15, is the
subject of the present invention.
[0021] The invention will be better understood from the following detailed description of
embodiments thereof, given by way of non-limiting example with reference to the accompanying
drawings, in which:
- Fig. 1 is a diagrammatic cross-section plan view of an assembly of parts comprising
an anchorage tie rod which is anchored within a perforating hole by means of an anchorage
device for anchorage tie rods according to a currently preferred embodiment, such
an anchorage device being depicted in an anchorage configuration;
- Fig. 2 is a diagrammatic top plan view of the anchorage device in Fig. 1, inserted
in the hole in Fig. 1, in which the anchorage device is depicted in a first configuration;
- Fig. 3 is a diagrammatic front plant view in which the anchorage device in Fig. 1
is shown in cross section along the line A-A in Fig. 2 in the first configuration
in Fig. 2, and inserted in the perforating hole in Fig. 1;
- Fig. 4 is a diagrammatic plan view similar to Fig. 3, in which the anchorage device
is depicted in a different configuration with respect to Fig. 3;
- Fig. 5 is a diagrammatic plan view similar to Figures 3 and 4, in which the anchorage
device is depicted in a different configuration with respect to such drawings;
- Fig. 6 is a diagrammatic plan view similar to Figures 3 to 5, in which the anchorage
device is depicted in the configuration in Fig. 1;
- Fig. 7 is a view similar to Fig. 3, in which there is depicted a further embodiment
of an anchorage device for anchorage tie rods according to the present description;
- Fig. 8 is a diagrammatic cross-section plan view of an assembly of parts comprising
an anchorage tie rod which is anchored within a perforating hole by means of an anchorage
device for anchorage tie rods according to a further embodiment, such an anchorage
device being depicted in an anchorage configuration;
- Fig. 9 is a diagrammatic top plan view of the anchorage device in Fig. 8, inserted
in the perforating hole in Fig. 8, in which the anchorage device is depicted in a
rest configuration;
- Fig. 10 is a diagrammatic front plan view in which the anchorage device in Fig. 9
is shown in cross section along the line B-B in Fig. 9; and
- Fig. 11 is a diagrammatic plan view similar to Fig. 10, in which the anchorage device
is depicted in a different configuration with respect to Fig. 10.
[0022] In general, equal or similar elements are indicated by the same numerals in the accompanying
drawings. However, for increased clarity of the present description, certain equal
or similar elements related to different embodiments of the present invention may
be indicated also by different numerals.
[0023] Moreover, it is worth noting that in the following description, the term "radial"
or other similar terms used to define a part of an anchorage device according to the
present description refer to the translation direction of the body of the hydraulic
cylinder, or of the rod of the hydraulic cylinder, of the anchorage device.
[0024] First, with reference to Fig. 1, such a drawing shows an assembly of parts which
is indicated as whole with numeral 100. The assembly of parts 100 comprises an anchorage
tie rod 5 preferably including at least one strand 10, and more preferably a plurality
of strands 10, for example two strands 10 as shown in Fig. 1. According to a preferred
embodiment, the part of the tie rod 5 corresponding to the free length of the tie
rod 5 is protected by a smooth sheath 6.1 of the type in itself known, while the part
of the tie rod 5 corresponding to the active length of the tie rod 5 is protected
by a corrugated sheath 6.2 of the type in itself known. Moreover, assembly 100 comprises
an anchorage device 1 for anchorage tie rods according to a currently preferred embodiment,
and a head plate 15, or anchorage head 15, for anchoring the aforesaid tie rod. The
head plate 15, preferably made of metal material, is arranged at an input opening
T1 of a perforating hole H made in a ground G. Hole H has a side wall SW of hole and
a bottom BW of hole. In the example shown in the accompanying drawings, hole H is
made both through a contrast structure PI, such as e.g. a reinforced cement wall,
a partition wall, a bearing wall, etc., and through ground G. In particular, the head
plate 15 is arranged at the input opening T1 to allow the transfer of the stresses
onto the contrast structure P1.
[0025] The anchorage device 1 is suitable for being inserted into the perforating hole H
to allow anchoring the aforesaid anchorage tie rod. It is worth noting, as indicated
above, that the anchorage tie rod 5 in the example embodiment is a tie rod with strands,
i.e. a tie rod comprising, or consisting of, one or more strands 10. However, the
teachings of the present description may be applied in general to all types of anchorage
tie rods, such as for example and not limited to, bar tie rods, cable tie rods, tube
tie rods, etc.
[0026] The anchorage tie rod 5, the anchorage device 1 and the head plate 15 in Fig. 1 are
depicted in the respective final anchoring configuration. As may be noted in Fig.
1, the tie rod 5 has each a respective end fixed to the anchorage device 1 and an
opposite end fixed to plate 15, preferably by means of a locking clamp 16. In other
words, in the example, each of the strands 10 has a respective end fixed to the anchorage
device 1 and an opposite end fixed to plate 15, preferably by means of a respective
locking clamp 16.
[0027] With reference to Figures 2 to 3, the anchorage device 1 comprises a hydraulic cylinder
20, 30, which in turn comprises a cylinder body 20 and a cylinder rod 30. Rod 30 is
slidably mounted to body 20. The cylinder body 20 comprises a cylinder chamber 201,
or expansion chamber 201, which is suitable for receiving a pressurized hydraulic
fluid F, preferably pressurized oil F. According to a preferred embodiment, fluid
F is input into chamber 201 by means of at least one input tube 11 (Fig. 1) communicating
with chamber 201. Rod 30 comprises a first end portion 301 of rod received in chamber
201 and a second end portion 302 of rod opposite to the first end portion 301. Portion
301 comprises a thrust wall 301A suitable for receiving the thrust of fluid F. To
this end, it is worth noting that the actual thrust surface of wall 301A corresponds
to an area equal to the area of a section orthogonal to rod 30 which is intermediate
between the end portions 301, 302. In other words, with reference to the example shown
in Figures 1 to 6, the radially projecting portion of wall 301A does not contribute
to the thrust on rod 30. Body 20 comprises a first end portion 202 of cylinder for
connecting the hydraulic cylinder 20, 30 to the aforesaid anchorage tie rod 5, an
opposite second end portion 203 of cylinder suitable for being operatively crossed
by rod 30 and a cylinder side wall 204, or cylinder jacket 204, interposed between
said first and second end portions 202, 203. According to a preferred embodiment,
the second end portion 203 comprises a connection plate 203 which is fixed, and more
preferably is welded, to the side wall 204. The anchorage device 1, comprises at least
two penetrating and anchorage plates 40, preferably made of metal material, e.g. steel,
which are hinged to body 20, and more preferably to the connection plate 203. In particular,
as may be noted in Fig. 3, the anchorage device 1 comprises at least one pair of plates
40 opposed with respect to body 20, i.e. arranged on two opposite sides of body 20.
With reference to Fig. 2, according to a preferred embodiment, the anchorage device
1 comprises four penetrating and anchorage plates 40 which are opposed two-by-two
with respect to body 20. Each penetrating and anchorage plate 40 has a free end portion
401 of penetration. According to a convenient embodiment, the free ends 401 are sharp
ends.
[0028] With reference to Fig. 3, the anchorage device 1 comprises a contrast base 50. Preferably,
base 50 is a plate-shaped base. Base 50 is associated with the second end portion
302 of rod 30 to allow the anchorage device 1 to be rested on the bottom BW of hole
H. According to one embodiment, base 50 is fixed to the end portion 302 of rod 30
preferably by means of at least one fastening screw 501.
[0029] Again with reference to Fig. 3, the anchorage device 1 comprises a movement mechanism
60 to allow the movement of the penetrating and anchorage plates 40. The movement
mechanism 60 comprises a mechanism portion 601 which is operatively connected to the
penetrating and anchorage plates 40 and is suitable for being operatively crossed
by the cylinder rod 30 so as to allow a relative sliding between such a mechanism
portion 601 and rod 30. Portion 601 in particular is arranged between the contrast
base 50 and the second end portion 203 of cylinder. According to a preferred embodiment,
portion 601 comprises a mechanism plate 601 comprising a plate hole 603 crossed by
rod 30.
[0030] The anchorage device 1 is suitable for taking on a relatively compact rest configuration
(Fig. 3), in which the penetrating and anchorage plates 40 take on a first angular
position in which they are facing the side wall 204 of body 20. Moreover, the anchorage
device 1 is suitable for taking on an anchorage configuration (Fig. 1 and Fig. 6)
which is relatively unfolded with respect to the rest configuration, in which the
penetrating and anchorage plates 40 take on a second angular position, different from
the first angular position.
[0031] The anchorage device 1 comprises an abutment portion 205 which preferably comprises
an abutment wall 205 of plate 203. The abutment wall 205 is located within body 20.
The movement mechanism 60 comprises a stroke end element 602 which is integral with
the portion 601 of mechanism 60. The stroke end element 602 preferably comprises a
stroke end wall 602 and is suitable for abutting against the abutment portion 205
to stop the penetrating and anchorage plates 40 in the aforesaid anchorage configuration
(Fig. 6).
[0032] Again with reference to Fig. 3, the movement mechanism 60 comprises at least one
distancing element 610, 70 operatively connected to portion 601 and arranged so as
to allow such a mechanism portion 601 to move away from the second end portion 203
of cylinder when the hydraulic fluid F is input into chamber 201.
[0033] Again with reference to Fig. 3, according to a convenient embodiment, the aforesaid
at least one distancing element 610, 70 comprises a sleeve member 610. According to
a convenient embodiment, the sleeve member 610 is partly extended within body 20 and
comprises a portion 611 of sleeve member which defines a movable wall 611 of chamber
201. This advantageously allows a more compact anchorage device to be made which requires
less pressure of fluid F to actuate the anchorage device and to allow the penetration
of the penetrating and anchorage plates 40 through the side wall SW of hole H with
respect to the second embodiment of the anchorage device (Fig. 7), which will be described
below in the present description.
[0034] According to a convenient embodiment, portion 611 has a thrust surface which is equal
to about three times the above-mentioned actual thrust surface of the thrust wall
301A. The sleeve member 610 is integral with portion 601 and comprises the stroke
end element 602. According to a preferred embodiment, the sleeve member 610 has a
radially projecting end flange which comprises the stroke end wall 602 and the movable
wall 611. The sleeve member 610 is coaxial to rod 30 and is slidably mounted to the
second end portion 203 of the cylinder. Rod 30 is suitable for sliding through the
sleeve member 610. According to a preferred embodiment, seal elements (not depicted)
are provided between the sleeve member 610 and the side wall 204 of body 20.
[0035] According to a preferred embodiment, the aforesaid at least one distancing element
610, 70 may comprise a resistance 70 to the sliding of portion 601, or brake 70, which
is integral with portion 601 or the sleeve member 610 and is suitable for engaging
or operatively contacting rod 30. For example, brake 70 may comprise a pair of jaws
rigidly connected to portion 601 and suitable for tightening rod 30 so as to contrast
the relative sliding between rod 30 and portion 601. In the example shown, brake 70
is arranged between portion 601 and portion 203. However, according to an alternative
embodiment, brake 70 may be arranged between portion 601 and base 50.
[0036] Again with reference to Fig. 3, according to a preferred embodiment, the movement
mechanism 60 comprises a plurality of connection linkages 620 which are interposed
between the mechanism portion 601 and the penetrating and anchorage plates 40. According
to a preferred embodiment, such connection linkages 620 comprise a plurality of connection
plates 620, for example one connection plate 620 for each penetrating and anchorage
plate 40. Mechanism 60 further comprises a first and a second connection hinge 621,
622 arranged to connect each connection linkage 620 to portion 601 and to one of the
penetrating and anchorage plates 40, respectively. According to a convenient embodiment,
each penetrating and anchorage plate 40 comprises a seat 402 suitable for at least
partly receiving one of the aforesaid second connection hinges 622 so as to reduce
or eliminate the radial projection of such a second connection hinge 622 beyond the
respective penetrating and anchorage plate 40 in the aforesaid rest configuration
of device 1. According to a preferred embodiment, seat 402 is made by shaping the
penetrating and anchorage plates 40 so that such plates have a bayonet profile, as
shown for example in Fig. 3. It is worth noting that the fact of reducing the radial
projection of the hinges 622 in the rest configuration conveniently allows increasing
the penetration efficiency of the plates 40 because it avoids the hinges 622 from
coming into contact with the side wall SW of hole H before the free ends 401 of penetration
of the plates 40.
[0037] The structure of the anchorage device 1 and assembly 100 being described, now there
is described a method of using device 1 with reference to the embodiment shown in
the accompanying Figures 1 to 6.
[0038] First, the anchorage device 1, connected to the tie rod 5, is inserted into the perforating
hole H by resting the contrast base 50 on bottom BW of such a hole. Once rested on
bottom BW, device 1 takes on the rest configuration in Fig. 3. Device 1 is then actuated
by inputting the pressurized fluid F into chamber 201 by means of the input tube 11.
The pressure of fluid F on portion 611 of the sleeve member 610 has the effect of
the sleeve member 610, and accordingly of plate 601 which is integral with the sleeve
member 610, sliding towards the bottom BW of hole H. The distancing of the plate 601
of mechanism 60 from the connection plate 203 results in the initial opening of the
penetrating and anchorage plates 40 which take on a third angular position (shown
in Fig. 4), which is intermediate between the aforesaid first angular position (Fig.
3) and second angular position (Fig. 1 or Fig. 6). It is worth noting that according
to a preferred embodiment, in the passage from the first angular position to the third
angular position of the plates 40, the distancing between plate 601 and the connection
plate 203 is very limited, for example equal to about 10 mm. It is also worth noting
that although the penetrating and anchorage plates 40 in Fig. 4 are depicted with
the respective free ends 401 of penetration resting on the side wall SW of hole H,
the free ends 401 of the plates 40 preferably press against the side wall SW and more
preferably partly penetrate through the side wall SW in the third angular position.
[0039] Continuing to input the pressurized fluid F into chamber 201 from the aforesaid third
angular position of the plates 40, since rod 30 cannot translate towards the bottom
of hole H because the contrast base 50 contrasts with the bottom BW of hole H, a translation
occurs of the cylinder body 20 in the distancing direction X1 from the bottom BW of
hole H, while rod 30 remains stopped. Accordingly, there is a translation in direction
X1 also of the plate 601 of mechanism 60 and of the penetrating and anchorage plates
40. To this end, it is worth noting that during the translation of body 20 in direction
X1, due to the effect of the thrust of fluid F on portion 611 of the sleeve member
610, such a sleeve 610 continues to be thrusted in direction opposite to direction
X1, i.e. towards the bottom BW of hole H. Accordingly, the translation in direction
X1 of the plate 601 of mechanism 60 is slowed down or braked with respect to the translation
in direction X1 of body 20, and more specifically with respect to the translation
of the connection plate 203. Thereby, during the translation of body 20 in direction
X1, plate 601 progressively moves away from the connection plate 203, thus allowing
a further spreading or umbrella opening of the plates 40 and accordingly, the penetration
of such plates 40 through the side wall SW of hole H. To this end, it is worth noting
that the penetration of the plates 40 through the side wall SW occurs at least partly
diagonally due to the effect of the translation of body 20 in direction X1, in the
sense that the plates 40 penetrate through the side wall SW both in lateral direction,
i.e. in direction orthogonal to direction X1, and in direction X1. It is worth noting
that when present, brake 70 allows the mutual distancing of plate 203 and of portion
601, and accordingly the penetration of the plates 40 through wall SW, to be further
facilitated.
[0040] Fig. 5 shows the anchorage device 1 in an intermediate penetration configuration
in which the plates 40 take on a fourth intermediate angular position between the
first angular position (Fig. 3) and the second angular position (Fig. 6). More specifically,
in the fourth angular position in Fig. 5, the plates 40 take on an intermediate angular
position between the third angular position (Fig. 4) and the second angular position
(Fig. 6). It may be noted in Fig. 5 that the plates 40 are more penetrated through
wall SW with respect to the configuration in Fig. 4. Moreover, the plates 601 and
plate 203 in Fig. 5 are more spaced apart from one another with respect to the configuration
in Fig. 4 and are also both more spaced apart from the contrast base 50 and from the
bottom BW of hole H with respect to the configuration of device 1 shown in Fig. 4.
[0041] Continuing to input the pressurized fluid into chamber 201 from the configuration
in Fig. 5, device 1 reaches the anchorage configuration in Fig. 6. As may be noted
in Fig. 6, according to a preferred embodiment, in the anchorage configuration, the
stroke end wall 602 abuts against the abutment wall 205 so as to stop the penetrating
and anchorage plates 40 in the second angular position while the plates 40 are arranged
orthogonal or substantially orthogonal with respect to direction X1, i.e. with respect
to the translation direction of body 20.
[0042] Practically, summarizing the above in relation to the operation of device 1, by inputting
the pressurized fluid F into chamber 201, device 1 goes from the rest configuration,
in which the penetrating and anchorage plates 40 preferably are parallel or substantially
parallel to the jacket 204 of the hydraulic cylinder, to the final anchorage configuration,
in which the plates 40 have performed their kinematism and are penetrated in the side
wall SW of hole H. Once the anchorage device 1 has taken on the anchorage configuration,
a cement mixture may be injected into hole H, thereby plugging the ground and filling
at least the stretch anchored, i.e. the stretch corresponding to device 1, with the
cement mixture.
[0043] Referring now to Fig. 7, such a drawing shows an anchorage device for anchorage tie
rods according to a second embodiment, which is indicated as a whole with numeral
1A. The anchorage device 1A in Fig. 7 is shown in a respective rest configuration
similar to the rest configuration of device 1 shown in Fig. 3. It is worth noting
that the anchorage device 1A differs from the anchorage device 1 essentially in that
it has a hydraulic cylinder having a slightly different cylinder body 20A with respect
to body 20, in that it has a longer cylinder rod 30A with respect to rod 30 and in
that it has a movement mechanism 60A for allowing the movement of the penetrating
and anchorage plates 40 which is slightly different with respect to the movement mechanism
60.
[0044] In particular, body 20A comprises a first end portion 202A of cylinder for connecting
the hydraulic cylinder to the aforesaid anchorage tie rod 5, an opposite second end
portion 203A of cylinder, or connection plate 203A, suitable for being operatively
crossed by rod 30A, and a cylinder side wall 204B, 204C, interposed between the first
and second end portions 202A, 203A of cylinder. In the example, the portions 202A
and 203A are identical to the portions 202, 203 of device 1 in Fig. 1. Body 20A comprises
at least one intermediate wall 203B which is arranged transversally to rod 30A and
is arranged in an intermediate position between the first and the second end portion
202A, 203A of cylinder. The intermediate wall 203B is operatively crossed by rod 30A.
According to a preferred embodiment, seal elements (not depicted) are operatively
interposed between the intermediate wall 203B and rod 30A. As may be noted in Fig.
7, body 20A comprises a first hollow portion 20B of cylinder and a second hollow portion
20C of cylinder. The first hollow portion 20B comprises a cylinder chamber 201A, or
expansion chamber 201A, suitable for receiving the pressurized hydraulic fluid F.
Chamber 201A is delimited by the end portion 202A, by the opposite intermediate wall
203B, and by a first portion 204B of side wall of the side wall 204B, 204C. The first
portion 204B is interposed between the end portion 202A and the intermediate wall
203B.
[0045] Rod 30A comprises a first end portion 301B of rod received in chamber 201A and a
second end portion 302A of rod, which is opposite to the first end portion 301B. The
aforesaid contrast base 50 is associated with the second end portion 302A.
[0046] The second hollow portion 20C extends from the intermediate wall 203B and is coaxial
with portion 20B. In particular, the second hollow portion 20C is defined by the intermediate
wall 203B, by the opposite second end portion 203A of cylinder and by a second portion
204C of side wall of the side wall 204B, 204C. Portion 204C is interposed between
the intermediate wall 203B and the second end portion 203A of cylinder.
[0047] Again with reference to Fig. 7, it is worth noting that mechanism 60A differs from
mechanism 60 only in that it provides a sleeve member 610A which is arranged in a
different manner with respect to the sleeve member 610, and accordingly has a partly
different operation with respect to the operation of the sleeve member 610. Indeed,
in the example the sleeve member 610A structurally is identical to the sleeve member
610 of device 1.
[0048] In particular, like the sleeve member 610, the sleeve member 610A is integral with
the mechanism portion 601 of mechanism 60A and comprises the aforesaid stroke end
element 602 which is suitable for abutting against an abutment portion 205A, or abutment
wall 205A, to stop the penetrating and anchorage plates 40 in an anchorage configuration
similar to the anchorage configuration of device 1 shown in Fig. 6. The sleeve member
610A is coaxial to rod 30A and is slidably mounted to the second end portion 203A.
Rod 30A is suitable for sliding through the sleeve member 610A. The substantial difference
between mechanism 60 and mechanism 60A is that the sleeve member 610A is arranged
outside chamber 201A. In particular, the sleeve member 610A is arranged partly within
the second hollow portion 20C and does not define a movable wall of chamber 201A.
[0049] It is also worth noting that in the case of the anchorage device 1A, the sleeve member
610A does not also perform the function of distancing the end portion 203A and the
portion 601 of mechanism 60A from each other. Indeed, in the case of device 1A, such
a function is performed only by the aforementioned brake 70.
[0050] The operation of the anchorage device 1A generally substantially is identical to
the operation of the anchorage device 1. The only operating difference between device
1 and device 1A lies essentially in the fact that, as mentioned above, the distancing
between the portion 601 of mechanism 60A and the connection plate 203A is due only
to brake 70. In other words, in the case of device 1A, the sleeve member 610A absolves
the function of stroke end by means of the stroke end element 602, while it does not
absolve the function of distancing portion 601 and the connection plate 203A from
each other. Practically, from the rest configuration of device 1A shown in Fig. 7,
the function of brake 70 is that of initially putting up a calibrated resistance to
the translation of body 20A in direction X1. Namely, from the configuration in Fig.
7, a translation is caused of body 20A in direction X1 when fluid F is input into
chamber 201A since rod 30A cannot slide towards bottom BW due to the fact that the
contrast base 50 is contrasting with bottom BW. Due to brake 70, initially portion
601 remains stopped (as well as the sleeve member 610A which is integral with the
latter), while plate 203A moves away from portion 601 translating in direction X1
so as to allow the penetrating and anchorage plates 40 to take on a configuration
similar to the configuration of device 1 shown in Fig. 4. From the latter configuration,
continuing to input fluid F into chamber 201A, body 20A continues to translate in
direction X1 together with the plates 40 and portion 601 until device 1A takes on
an anchorage configuration similar to the anchorage configuration of device 1 shown
in Fig. 1 and Fig. 6. In particular, during such a translation of body 20A, since
portion 601 is partly braked by brake 70, the connection plate 203A and portion 601
continue moving away from each other so as to allow the umbrella opening of the penetrating
and anchorage plates 40, and accordingly the penetration of the penetrating and anchorage
plates 40 through the side wall SW. It is worth noting that the umbrella opening of
the plates 40 is also facilitated by the pressure of the plates 40 on the side wall
SW in the configuration similar to the configuration in Fig. 4. It is also worth noting,
as described above in relation to the operation of the anchorage device 1, during
the translation of body 20A in direction X1, the penetrating and anchorage plates
40 penetrate the wall SW of hole H diagonally, i.e. both laterally and in direction
X1. Once the installation of device 1A is complete, as in the case of device 1, the
injection may be proceeded with, thus plugging the ground and filling at least the
anchored stretch with cement mixture.
Generalizing the above description, a process has therefore been described for anchoring
anchorage tie rods, comprising:
- A) a step of providing an anchorage device (1; 1A) and an anchorage tie rod (10) connected
to the anchorage device (1; 1A), the anchorage device (1; 1A) comprising:
- a hydraulic cylinder comprising a cylinder body (20; 20A) and a cylinder rod (30;
30A) slidably mounted to the cylinder body (20; 20A), the cylinder body (20; 20A)
comprises a cylinder chamber (201; 201A) suitable for receiving a pressurized hydraulic
fluid (F), the cylinder rod (30; 30A) comprises a first end portion (301; 301A) of
rod received in the cylinder chamber (201; 201A) and a second end portion (302; 302A)
of rod opposite to the first end portion (301; 301A) of rod, said cylinder body (20;
20A) comprises a first end portion (202; 202A) of cylinder for connecting the hydraulic
cylinder to said at least one anchorage tie rod (10), an opposite second end portion
(203; 203A) of cylinder suitable for being operatively crossed by the cylinder rod
(30; 30A) and a cylinder side wall (204; 204B, 204C) interposed between said first
and second end portions (202, 203; 202A, 203A) of cylinder;
- at least two penetrating and anchorage plates (40) hinged to the cylinder body (20;
20A), each penetrating and anchorage plate (40) having a free end portion (401) of
penetration;
- a contrast base (50) associated with said second end portion (302; 302A) of rod to
allow the anchorage device (1; 1A) to be rested on a bottom (BW) of a perforating
hole (H);
- a movement mechanism (60; 60A) for allowing the movement of the penetrating and anchorage
plates (40), said movement mechanism (60; 60A) comprising a mechanism portion (601)
which is operatively connected to the penetrating and anchorage plates (40) and is
suitable for being operatively crossed by the cylinder rod (30; 30A) so as to allow
a relative sliding between such a mechanism portion (601) and the cylinder rod (30;
30A), said mechanism portion (601) being arranged between said contrast base (50)
and said second end portion (203; 203A) of cylinder;
said anchorage device (1; 1A) being suitable for taking on
a relatively compact rest configuration, in which the penetrating and anchorage plates
(40) take on a first angular position in which they are facing the cylinder side wall
(204; 204B, 204C); and
an anchorage configuration which is relatively unfolded with respect to the rest configuration,
in which the penetrating and anchorage plates (40) take on a second angular position,
different from the first angular position;
in which the anchorage device (1; 1A) comprises an abutment portion (205; 205A) and
the movement mechanism (60; 60A) comprises a stroke end element (602) which is integral
with said mechanism portion (601) and which is suitable for abutting against said
abutment portion (205; 205A) in order to stop the penetrating and anchorage plates
(40) in said anchorage configuration;
in which the movement mechanism (60; 60A) comprises at least one distancing element
(610, 70) operatively connected to said mechanism portion (601) and arranged so as
to allow said mechanism portion (601) to move away from the second end portion (203;
203A) of cylinder when the hydraulic fluid (F) is input into the cylinder chamber
(201; 201A);
- B) a step of inserting the anchorage device (1; 1A) connected to said tie rod (10)
into said perforating hole (H) and resting said contrast base (50) on the bottom (BW)
of said perforating hole (H);
- C) a first step of inputting said hydraulic fluid (F) into said cylinder chamber (201;
201A) so as to move said mechanism portion (601) away from said second end portion
(203; 203A) of cylinder by means of said distancing element (610, 70), in order to
cause said penetrating and anchorage plates (40) to take on a third intermediate angular
position between said first and second angular position, the free ends (401) of penetration
of the penetrating and anchorage plates (40) pressing or partly penetrating the side
wall (SW) of the perforating hole in said third angular position;
and
- D) a second step of inputting said hydraulic fluid (F) into said cylinder chamber
(201; 201A) so as to cause a translation of the cylinder body (20; 20A), said mechanism
portion (601) and the penetrating and anchorage plates (40) in the distancing direction
(X1) from the bottom (BW) of the perforating hole (H) so as to allow the penetrating
and anchorage plates (40) to further penetrate through the side wall (SW) of the perforating
hole (H) and so as to cause such plates (40) to take on said anchorage configuration.
[0051] Based on the above description, it may be understood how an anchorage device according
to the present invention is such as to resolve the above-mentioned drawbacks with
reference to the known art.
[0052] The features of an anchorage device according to the present description indeed meet
the need to increase the efficiency of transferring loads to the ground while almost
completely eliminating the extraction problems of the tie rod. Indeed, the anchoring
no longer occurs by relying on the friction resistance due to the mortar-ground adhesion,
rather it is ensured by the mechanical resistance of the penetrating and anchorage
plates which are first driven into the walls of the perforating hole and then embedded
with slurry. Therefore, with such a device, it will be more than sufficient to penetrate
about 3 to 4 meters into the active stretch (thus drastically reducing the active
length which as mentioned above, generally may also reach 40 meters for conventional
tie rods), proceed with opening by actuating the cylinder rod and once penetration
is complete, inject cement grout.
[0053] Once anchored, the system can no longer be removed because the penetrating and anchorage
plates, which are now spread and penetrated in the side wall of the hole, have an
open diameter which is much greater than the diameter of the perforation, thus achieving,
as mentioned, a mechanical type anchoring and no longer a friction anchoring.
[0054] With reference now to Fig. 8, such a drawing shows an assembly of parts which is
indicated as whole with numeral 100E. The assembly of parts 100E comprises an anchorage
tie rod 5 preferably including at least one strand 10, and more preferably a plurality
of strands 10, for example two strands 10 as shown in Fig. 8. According to a preferred
embodiment, the part of the tie rod 5 corresponding to the free length of the tie
rod 5 is protected by a smooth sheath 6.1 of the type in itself known, while the part
of the tie rod 5 corresponding to the active length of the tie rod 5 is protected
by a corrugated sheath 6.2 of the type in itself known. Moreover, assembly 100E comprises
an anchorage device 1E for anchorage tie rods according to a further embodiment, and
a head plate 15, or anchorage head 15, for anchoring the aforesaid tie rod 5. The
head plate 15, preferably made of metal material, is arranged at an input opening
T1 of a perforating hole H made in a ground G. Hole H has a side wall SW of hole and
a bottom BW of hole. In the example shown in the accompanying drawings, hole H is
made both through a contrast structure PI, such as e.g. a reinforced cement wall,
a partition wall, a bearing wall, etc., and through ground G. In particular, the head
plate 15 is arranged at the input opening T1 to allow the transfer of the stresses
onto the contrast structure P1.
[0055] The anchorage device 1E is suitable for being inserted into the perforating hole
H to allow anchoring the aforesaid anchorage tie rod. It is worth noting, as indicated
above, that the anchorage tie rod 5 in the example embodiment is a tie rod with strands,
i.e. a tie rod comprising, or consisting of, one or more strands 10. However, the
teachings of the present description may be applied in general to all types of anchorage
tie rods, such as for example and not limited to, bar tie rods, cable tie rods, tube
tie rods, etc.
[0056] The anchorage tie rod 5, the anchorage device 1E and the head plate 15 in Fig. 8
are depicted in the respective final anchoring configuration. As may be noted in Fig.
8, the tie rod 5 has a respective end fixed to the anchorage device 1E and an opposite
end fixed to plate 15, preferably by means of at least one locking clamp 16. In other
words, each of the strands 10 in the example has a respective end fixed to the anchorage
device 1E and an opposite end fixed to plate 15, preferably by means of a respective
locking clamp 16. With reference to figures Fig. 8 to Fig. 11, the anchorage device
1E comprises a hydraulic cylinder having a middle axis Z1. Such a hydraulic cylinder
comprises a cylinder body 20E and a cylinder rod 30E slidably mounted to the cylinder
body 20E. The middle axis Z1 practically corresponds to the translation direction
of body 20E or of rod 30E. The cylinder body 20E comprises a first cylinder chamber
201E, or first expansion chamber 201E, suitable for receiving a pressurized hydraulic
fluid F (such a fluid is depicted by means of small lines in Fig. 8 and Fig. 11).
Fluid F may be input into the first chamber 201E preferably by means of at least one
tube (not depicted) communicating with chamber 201E. The cylinder rod 30E comprises
a first end portion 301E of rod received in the first cylinder chamber 201E and a
second end portion 302E of rod, which is opposite to the first end portion 301E. The
cylinder body 20E comprises a first end portion 202E of cylinder, an opposite second
end portion 203E of cylinder suitable for being operatively crossed by rod 30E, and
a cylinder side wall 204E interposed between said first and second end portions 202E,
203E of cylinder. Preferably, the first end portion 202E comprises an end plate 202E
of cylinder. The anchorage device 1E comprises at least two penetrating and anchorage
plates 40, preferably four plates 40 opposed two-by-two as shown in Fig. 9. Each penetrating
and anchorage plate 40 has a free end portion 401 of penetration. The anchorage device
1E further comprises a contrast base 50 associated with the second end portion 302E
of rod to allow the anchorage device 1E to be rested on a bottom BW of hole H. Again,
the anchorage device 1E comprises a movement mechanism 60E operatively connected to
the hydraulic cylinder to allow the movement of the penetrating and anchorage plates
40. The movement mechanism 60E comprises a mechanism portion 601E, preferably a mechanism
plate 601E, to which the penetrating and anchorage plates 40 are hinged and to which
the anchorage tie rod 5 is suitable for being connected. Portion 601E is arranged
facing the first end portion 202E of cylinder.
[0057] The anchorage device 1E is suitable for taking on a relatively compact rest configuration
(Fig. 10). In such a rest configuration, the penetrating and anchorage plates 40 project
from the mechanism portion 601E on the opposite side with respect to the contrast
base 50. Moreover, in such a rest configuration, the plates 40 take on a first angular
position in which they are arranged parallel or substantially parallel to the middle
axis Z1 of the hydraulic cylinder.
[0058] The anchorage device 1E is also suitable for taking on an anchorage configuration
(Fig. 8) which is relatively unfolded with respect to the rest configuration (Fig.
10). In the anchorage configuration, the penetrating and anchorage plates 40 take
on a second angular position, different from the first angular position. According
to one embodiment, in the anchorage configuration, the plates 40 are extended orthogonally
or substantially orthogonally with respect to the middle axis Z1 of the hydraulic
cylinder.
[0059] Again with reference to Fig. 8 to Fig. 11, the movement mechanism 60E comprises at
least one distancing element 610E operatively connected to the mechanism portion 601E.
The distancing element 610E is arranged so as to operatively cross the first end portion
202E of cylinder and to allow the mechanism portion 601E to move away from the first
end portion 202E of cylinder when the hydraulic fluid F is input into the first cylinder
chamber 201E so as to allow the movement of the penetrating and anchorage plates 40.
[0060] According to one embodiment, the at least one distancing element 610E comprises a
hollow longitudinal member 610E, or sleeve 610E, which is integral with the mechanism
portion 601E. The hollow longitudinal member 610E is coaxial to rod 30E and delimits
the first cylinder chamber 201E on the opposite side with respect to the second end
portion 203E of the cylinder. When the anchorage device 1E takes on the rest configuration,
the hollow longitudinal member 610E is suitable for receiving a portion of rod 30E
comprising the first end portion 301E of rod 30E. Preferably, member 610E has a respective
end 612E fixed, for example welded, directly to portion 601E. Preferably, such an
end 612E of member 610E is a wall 612E which closes an end of the cavity of the hollow
longitudinal member 610E.
[0061] According to one embodiment, the hollow longitudinal member 610E comprises a radially
projecting longitudinal portion 611E of member which defines a movable wall of the
first cylinder chamber 201E.
[0062] According to one embodiment, the movement mechanism 60E comprises a plurality of
connection linkages 620 interposed between the first end portion 202E of cylinder
and the penetrating and anchorage plates 40. In particular, in the rest configuration,
said penetrating and anchorage plates 40 are arranged radially internal and said connection
linkages 620 are arranged radially external with respect to said penetrating and anchorage
plates 40.
[0063] According to a convenient embodiment, the movement mechanism 60E comprises a first
and a second connection hinges 621, 622 arranged to connect each connection linkage
620 to said first end portion 202E of cylinder and to one of said penetrating and
anchorage plates 40, respectively. In particular, each penetrating and anchorage plate
40 comprises a seat 402 suitable for at least partly receiving said second connection
hinge 622 so as to reduce or eliminate the radial projection of the second connection
hinge 622 beyond the respective penetrating and anchorage plate 40 in the rest configuration
of the anchorage device 1E. This advantageously allows the radial volume of the anchorage
device to be reduced in the rest configuration.
[0064] It is worth noting that since rod 30E does not completely cross member 610E and the
mechanism portion 601E, the thrust surface of member 610E may be wholly taken advantage
of. Thereby, the opening and complete penetration of the plates 40 is obtained, thus
reducing the stroke of device 1E itself. All this results in having a particularly
short cylinder body 20E and therefore, in essence, the whole device 1E being particularly
short.
[0065] Moreover, it is worth noting that with the arrangement of member 610E, it becomes
possible to fasten the end 612E thereof to portion 601E to which the plates 40 are
hinged, while the linkages 620 may be hinged to the first end portion 202E of cylinder.
The advantage obtained is that, being beyond the first end portion 202E of cylinder,
portion 601E may be narrower than the outer diameter of the cylinder body 20E so that
in the rest configuration of device 1E, the radial volume of the plates 40, linkages
620 and hinges 621, 622 does not exceed, or exceeds to a limited extent, beyond the
outer diameter of the cylinder body 20E. This results in a particularly reduced radial
volume of the whole device 1E.
[0066] According to a convenient embodiment, the cylinder body 20E comprises a second cylinder
chamber 207E suitable for receiving the pressurized hydraulic fluid F. The second
chamber 207E is opposite to the first cylinder chamber and is delimited by the distancing
element 610E on the side opposite to the first end portion 202E of cylinder. The distancing
element 610E is arranged so as to allow the mechanism portion 601E to move close to
the first end portion 202E of cylinder when the hydraulic fluid F is input into the
second cylinder chamber 207E so as to allow the movement of the penetrating and anchorage
plates 40 to cause the anchorage device 1E to take on the rest configuration. It is
worth noting that the space or distance between the radially projecting portion 611E
and the first end portion 202E of cylinder in Fig. 8 was depicted significantly enlarged
with respect to the actual condition so as to be able to depict the second chamber
207E. However, in the configuration in Fig. 8, portion 611E is abutting or substantially
abutting against the first end portion 202E of cylinder.
[0067] In essence, according to a convenient embodiment, the anchorage device 1E comprises
a dual effect hydraulic cylinder which, as will be better understood below in the
description, in the case of erroneous placement of the anchorage device 1E (obviously
before the injection with grout), allows bringing it back to the rest configuration
and extracting it from hole H.
[0068] According to a preferred embodiment, the anchorage device 1E comprises a resistance
70E, or brake 70E, to the relative sliding between the cylinder body 20E and rod 30E.
Brake 70E is integral with the cylinder body 20E, and more preferably is integral
with the second end portion 203E of cylinder, and is suitable for engaging or operatively
contacting rod 30E. For example, brake 70E may comprise a pair of jaws rigidly connected
to the second end portion 203E and suitable for tightening rod 30E so as to contrast
the relative sliding between rod 30E and the cylinder body 20E. Preferably, brake
70E is arranged between the second end portion 203E of cylinder and the contrast base
50.
[0069] The structure of the anchorage device 1E and assembly 100E being described, now there
is described a method of using device 1E with reference to the embodiment shown in
the accompanying Figures 8 to 11.
[0070] First, the anchorage device 1E, connected to the tie rod 5, is inserted into the
perforating hole H by resting the contrast base 50E on bottom BW of such a hole. Once
rested on bottom BW, device 1E takes on the rest configuration in Fig. 10. Device
1E is actuated by initially inputting the pressurized fluid F into the first chamber
201E. The pressure of fluid F on the thrust surface of rod 30E and on the thrust surface
of the hollow longitudinal member 610E has as effect the relative sliding of rod 30E
with respect to member 610E, with member 610E translating in direction X1.
Indeed, since the contrast base 50 contrasts with the bottom BW of hole H, rod 30E
does not have the possibility to move and therefore the aforesaid sliding may only
cause a translation in direction X1 of member 610E. Portion 601E, which is integral
with member 610E, translates in direction X1 due to the effect of the translation
in direction X1 of member 610E itself. Then, as will be better explained below, also
the cylinder body 20E starts to translate in direction X1. Such a rectilinear motion
in direction X1 of the first end portion 202E of cylinder and of portion 601E induces
the umbrella opening of the linkages 620 and of the penetrating and anchorage plates
40.
[0071] In essence, there is a kinematism which transforms the rectilinear motion in direction
X1 of the cylinder body 20E and of member 610E both into a translation in direction
X1 of the linkages 620 and of the plates 40 and a spreading of such linkages 620 and
plates 40 towards the side wall SW of hole H.
[0072] The function of brake 70E is that of initially putting up a calibrated resistance
to the translation of cylinder body 20E in direction X1. Namely, considering that
the thrust surface of the hollow longitudinal member 610E preferably is about 5 to
8 times greater than the thrust surface of rod 30E, and also since the translation
of the cylinder body 20E is initially locked by brake 70E, due to the translation
of member 610E, the result is, in a first step, only the spreading takes place of
the linkages 620 and of the penetrating and anchorage plates 40 which press the side
wall SW of hole H. At this point, device 1E takes on for example, the configuration
in Fig. 11. Then, continuing to input fluid F into the first chamber 201E, once the
resistance of brake 70E is overcome, and due also to the fact that the plates 40 press
against the side wall SW of hole H, also the cylinder body 20E starts to slide in
direction X1 in addition to member 610E. Accordingly, due to the opposition of the
contrast base 50 and to the pressure of the penetrating and anchorage plates 40 on
the side wall SW of hole H both in direction X1 and in radial direction, the penetration
thereof in hole H is facilitated.
[0073] Therefore, by inputting the pressurized fluid F into the first chamber 201E and due
to the above-mentioned action of brake 70E, the anchorage device 1E goes from the
rest configuration in Fig. 10, in which the plates 40 and the linkages 620 are parallel
to the middle axis Z1, to an intermediate configuration (Fig. 11), in which penetrating
and anchorage plates 40 take on a third intermediate angular position (Fig. 11) between
the first angular position (Fig. 10) and the second angular position (Fig. 8). In
such a third angular position, the free ends 401 of penetration of the penetrating
and anchorage plates 40 press or partly penetrate the side wall SW of the perforating
hole.
[0074] From the aforesaid intermediate configuration of device 1E, continuing to input the
pressurized fluid F into the first chamber 201E, fluid F, acting as already mentioned
above on the thrust surfaces of the hollow longitudinal member 610E, causes the translation
of member 610E in direction X1. As already mentioned above, also the cylinder body
20E translates in direction X1 up to bringing device 1E into the anchorage configuration
in which the penetrating and anchorage plates 40 have performed their kinematism and
are penetrated in the side wall SW of hole H.
[0075] Once the installation of device 1E is complete, the injection with cement mixture
into hole H may be proceeded with, thus plugging the ground and filling the stretch
anchored with cement mixture.
[0076] It is worth noting that due to the fact of providing the second chamber 207E, if,
during the placement operations of device 1E, and in any case before injecting cement
grout, the operator realizes to have made a mistake during the installation of the
tie rod 5 in hole H and would like to extract it, device 1E has the features to allow
this to be done.
[0077] Indeed, by inputting pressurized fluid F into the second chamber 207E, the pressure
of fluid F has the effect of exerting a thrust on the radially projecting portion
611E of member 610E, thus causing the translation of member 610E in opposite direction
with respect to direction X1, i.e. towards the bottom BW of hole H, and the discharge
from the first chamber 201E of fluid F in such a first chamber 201E. Accordingly,
since portion 601E is fixed to the hollow member 610E, the plates 40 move up to taking
on an identical or substantially identical angular position to that in Fig. 10. To
this end, it is worth noting however that by inputting the pressurized fluid F into
the second chamber 207E, only the translation of member 610E is induced in the direction
opposite to direction X1, and not also the translation of the cylinder body 20E in
direction opposite to direction X1. Thus, the effect of the retraction of member 610E
which is integral with portion 601E only closes the plates 40. In other words, once
the plates 40 are closed again, rod 30E will still be extracted from the cylinder
body 20E. At this point, the tie rod 5 and device 1E may be extracted from hole H.
Once device 1E has been extracted from hole H, to bring device 1E itself into the
initial rest configuration, brake 70E is to be loosened and rod 30E is to be returned,
e.g. manually, into the cylinder body 20E.
[0078] Generalizing the above description in relation to the anchorage device 1E, a process
has therefore been described for anchoring anchorage tie rods, comprising:
- A) a step of providing an anchorage device (1E) suitable for being inserted into a
perforating hole (H) made in a ground, and an anchorage tie rod (5) connected to the
anchorage device (1E), the anchorage device (1E) comprising:
- a hydraulic cylinder having a middle axis (Z1) and comprising a cylinder body (20E)
and a cylinder rod (30E) slidably mounted to the cylinder body (20E), the cylinder
body (20E) comprises a first cylinder chamber (201E) suitable for receiving a pressurized
hydraulic fluid (F), the cylinder rod (30E) comprises a first end portion (301E) of
rod received in the cylinder chamber (201E) and a second end portion (302E) of rod
opposite to the first end portion (301E) of rod, said cylinder body (20E) comprises
a first end portion (202E) of cylinder, an opposite second end portion (203E) of cylinder
suitable for being operatively crossed by the cylinder rod (30E) and a cylinder side
wall (204E) interposed between said first and second end portions (202E, 203E) of
cylinder;
- at least two penetrating and anchorage plates (40), each penetrating and anchorage
plate (40) having a free end portion (401) of penetration;
- a contrast base (50) associated with said second end portion (302E) of rod to allow
the anchorage device (1E) to be rested on a bottom (BW) of said hole (H);
- a movement mechanism (60E) operatively connected to the hydraulic cylinder for allowing
the movement of the penetrating and anchorage plates (40), said movement mechanism
(60E) comprising a mechanism portion (601E) to which the penetrating and anchorage
plates (40) are hinged and to which said anchorage tie rod (5) is suitable for being
connected, said mechanism portion (601E) being arranged facing said first end portion
(202E) of cylinder;
said anchorage device (1E) being suitable for taking on
a relatively compact rest configuration, in which the penetrating and anchorage plates
(40) project from said mechanism portion (601E) on the side opposite to said contrast
base (50) and in which they take on a first angular position in which they are arranged
parallel or substantially parallel to the middle axis (Z1) of the hydraulic cylinder;
and
an anchorage configuration which is relatively unfolded with respect to the rest configuration,
in which the penetrating and anchorage plates (40) take on a second angular position,
different from the first angular position;
in which the movement mechanism (60E) comprises at least one distancing element (610E)
operatively connected to said mechanism portion (601E) and arranged so as to operatively
cross the first end portion (202E) of cylinder and to allow said mechanism portion
(601E) to move away from the first end portion (202E) of cylinder when the hydraulic
fluid (F) is input into the first cylinder chamber (201E) so as to allow the movement
of the penetrating and anchorage plates (40);
- B) a step of inserting the anchorage device (1E) connected to said tie rod (5) into
a perforating hole (H) and resting said contrast base (50) on a bottom (BW) of said
perforating hole (H);
- C) a first step of inputting said hydraulic fluid (F) into said first cylinder chamber
(201E) so as to move said mechanism portion (601E) away from said first end portion
(202E) of cylinder by means of said distancing element (610E), in order to cause said
penetrating and anchorage plates (40) to take on a third intermediate angular position
between said first and second angular position, the free ends (401) of penetration
of the penetrating and anchorage plates (40) pressing or partly penetrating a side
wall (SW) of the perforating hole (H) in said third angular position;
and
- D) a second step of inputting said hydraulic fluid (F) into said first cylinder chamber
(201E) so as to cause a translation of the cylinder body (20E), said mechanism portion
(601E) and the penetrating and anchorage plates (40), in the distancing direction
(X1) from the bottom (BW) of the perforating hole (H) so as to allow the penetrating
and anchorage plates (40) to further penetrate through the side wall (SW) of the perforating
hole (H) and so as to cause such plates (40) to take on said anchorage configuration.
[0079] The features of the anchorage device according to the present invention meet the
need to increase the efficiency of transferring loads to the ground while almost completely
eliminating the extraction problems of the tie rod. Indeed, the anchoring no longer
occurs by relying on the friction resistance due to the mortar-ground adhesion, rather
it is ensured by the mechanical resistance of the plates which are first driven into
the walls of the hole and then embedded with slurry. Therefore, with such a device,
it will be more than sufficient to penetrate about 3 to 4 meters into the active stretch
(thus drastically reducing the active length which, as mentioned above, generally
may also reach 40 meters for conventional tie rods).
[0080] Once anchored, the system can no longer be removed because the metal fins, which
are now spread and penetrated in the walls of the hole, have an open diameter which
is much greater than the diameter of the perforation, thus achieving, as mentioned,
a mechanical type anchoring and no longer a friction anchoring.
[0081] Due to the anchorage achieved with the driving in of the penetrating and anchorage
plates, the traditional and uncertain action of bulbs obtained with injections may
be eliminated. The metal fins actuated by sliding the cylinder rod have a significant
penetration force which allows them to be inserted into any type of ground. The flexibility
of the system not only also allows the device proposed to be applied to anchorage
tie rods, but also to any other type of deep foundation.
[0082] In particular, the embodiment described with reference to Fig. 8 to Fig. 11 allows
for example, obtaining the following advantages in terms of execution times, safety,
the environment, and in terms of being economical and practical:
- shorter perforation lengths which result in a reduction both of costs and unforeseen
events and problems associated with the execution thereof;
- reduced diameter of perforation;
- smaller quantities of cement mortar per injection;
- improved environmental impact because a shallower excavation depth corresponds to
a smaller volume of debris to be disposed of;
- shorter active lengths result in simplicity of movement, storage at the site and transport;
- decreased execution times at the site, with advantages in terms of being economical
and workplace safety;
- injection only of the active part; while in commonly-used tie rods, primary, secondary
injections of the filling bag, etc. become necessary;
- application substantially in all types of ground, from the poorest to the most solid
ones;
- elimination of uncertainties associated with the friction hold of the foundation bulbs
because the mechanical hold of the present device provides increased guarantees.
[0083] It is apparent that modifications and/or variants may also be made to the above description
disclosed above by way of example.
[0084] For example, it is worth noting that the accompanying drawings to the present description
are only given by way of example. Indeed, for example the dimensions both of the penetrating
and anchorage plates and of the relative connection linkages (width, length and thickness)
which in essence determine the contrast surface with the ground, may also be sized
each time according to the type of ground itself. It is apparent that the less the
resistance of the ground, the greater the contact surface is to be, and vice versa.
[0085] The principle of the invention being understood, the embodiments and manufacturing
details may largely vary with respect to those described and disclosed by mere way
of non-limiting example, without departing from the scope of the invention as defined
in the appended claims.
1. An anchorage device (1; 1A) for anchorage tie rods, suitable for being inserted into
a perforating hole (H) made in a ground to allow anchoring an anchorage tie rod (5),
comprising:
- a hydraulic cylinder comprising a cylinder body (20; 20A) and a cylinder rod (30;
30A) slidably mounted to the cylinder body (20; 20A), the cylinder body (20; 20A)
comprises a cylinder chamber (201; 201A) suitable for receiving a pressurized hydraulic
fluid (F), the cylinder rod (30; 30A) comprises a first end portion (301; 301A) of
rod received in the cylinder chamber (201; 201A) and a second end portion (302; 302A)
of rod opposite to the first end portion (301; 301A) of rod, said cylinder body (20;
20A) comprises a first end portion (202; 202A) of cylinder for connecting the hydraulic
cylinder to said anchorage tie rod (5), an opposite second end portion (203; 203A)
of cylinder suitable for being operatively crossed by the cylinder rod (30; 30A) and
a cylinder side wall (204; 204B, 204C) interposed between said first and second end
portions (202, 203; 202A, 203A) of cylinder;
- at least two penetrating and anchorage plates (40) hinged to the cylinder body (20;
20A), each penetrating and anchorage plate (40) having a free end portion (401) of
penetration;
- a contrast base (50) associated with said second end portion (302; 302A) of rod
to allow the anchorage device (1; 1A) to be rested on a bottom (BW) of said hole (H);
- a movement mechanism (60; 60A) for allowing the movement of the penetrating and
anchorage plates (40), said movement mechanism (60; 60A) comprising a mechanism portion
(601) which is operatively connected to the penetrating and anchorage plates (40)
and is suitable for being operatively crossed by the cylinder rod (30; 30A) so as
to allow a relative sliding between such a mechanism portion (601) and the cylinder
rod (30; 30A), said mechanism portion (601) being arranged between said contrast base
(50) and said second end portion (203; 203A) of cylinder;
said anchorage device (1; 1A) being suitable for taking on
a relatively compact rest configuration, wherein the penetrating and anchorage plates
(40) take on a first angular position wherein they are facing the cylinder side wall
(204; 204B, 204C); and
an anchorage configuration which is relatively unfolded with respect to the rest configuration,
wherein the penetrating and anchorage plates (40) take on a second angular position,
different from the first angular position;
wherein the anchorage device (1; 1A) comprises an abutment portion (205; 205A) and
the movement mechanism (60; 60A) comprises a stroke end element (602) which is integral
with said mechanism portion (601) and which is suitable for abutting against said
abutment portion (205; 205A) in order to stop the penetrating and anchorage plates
(40) in said anchorage configuration;
wherein the movement mechanism (60; 60A) comprises at least one distancing element
(610, 70) operatively connected to said mechanism portion (601) and arranged so as
to allow said mechanism portion (601) to move away from the second end portion (203;
203A) of cylinder when the hydraulic fluid (F) is input into the cylinder chamber
(201; 201A) .
2. An anchorage device (1; 1A) according to claim 1, wherein said movement mechanism
(60; 60A) comprises a sleeve member (610; 610A) which is integral with said mechanism
portion (601) and comprising said stroke end element (602), said sleeve member (610;
610A) being coaxial to the cylinder rod (30; 30A) and being slidably mounted to the
second end portion (203; 203A) of cylinder, the cylinder rod (30; 30A) being suitable
for sliding through said sleeve member (610; 610A).
3. An anchorage device (1) according to claim 2, wherein said distancing element (610,
70) comprises said sleeve member (610), said sleeve member (610) being partly extended
within the cylinder body (20) and comprising a portion (611) of sleeve member which
defines a movable wall of the cylinder chamber (201).
4. An anchorage device (1) according to any one of the preceding claims, wherein said
movement mechanism (60; 60A) comprises a plurality of connection linkages (620) interposed
between said mechanism portion (601) and said penetrating and anchorage plates (40),
and a first and a second connection hinges (621, 622) arranged to connect each connection
linkage (620) to said mechanism portion (601) and to one of said penetrating and anchorage
plates (40) respectively, each penetrating and anchorage plate (40) comprising a seat
(402) suitable for at least partly receiving said second connection hinge (622) so
as to reduce or eliminate, in said rest configuration, the radial projection of said
second connection hinge (622) beyond the respective penetrating and anchorage plate
(40).
5. An assembly of parts (1, 5, 15; 1A, 5, 15) comprising an anchorage tie rod (5), an
anchorage device (1) as defined in any one of the preceding claims, and a head plate
(15) for said tie rod (5).
6. A process for anchoring anchorage tie rods, comprising:
A) a step of providing an anchorage device (1; 1A) and an anchorage tie rod (5) connected
to the anchorage device (1; 1A), the anchorage device (1; 1A) comprising:
- a hydraulic cylinder comprising a cylinder body (20; 20A) and a cylinder rod (30;
30A) slidably mounted to the cylinder body (20; 20A), the cylinder body (20; 20A)
comprises a cylinder chamber (201; 201A) suitable for receiving a pressurized hydraulic
fluid (F), the cylinder rod (30; 30A) comprises a first end portion (301; 301A) of
rod received in the cylinder chamber (201; 201A) and a second end portion (302; 302A)
of rod opposite to the first end portion (301; 301A) of rod, said cylinder body (20;
20A) comprises a first end portion (202; 202A) of cylinder for connecting the hydraulic
cylinder to said anchorage tie rod (5), an opposite second end portion (203; 203A)
of cylinder suitable for being operatively crossed by the cylinder rod (30; 30A) and
a cylinder side wall (204; 204B, 204C) interposed between said first and second end
portions (202, 203; 202A, 203A) of cylinder;
- at least two penetrating and anchorage plates (40) hinged to the cylinder body (20;
20A), each penetrating and anchorage plate (40) having a free end portion (401) of
penetration;
- a contrast base (50) associated with said second end portion (302; 302A) of rod
to allow the anchorage device (1; 1A) to be rested on a bottom (BW) of a perforating
hole (H);
- a movement mechanism (60; 60A) for allowing the movement of the penetrating and
anchorage plates (40), said movement mechanism (60; 60A) comprising a mechanism portion
(601) which is operatively connected to the penetrating and anchorage plates (40)
and is suitable for being operatively crossed by the cylinder rod (30; 30A) so as
to allow a relative sliding between such a mechanism portion (601) and the cylinder
rod (30; 30A), said mechanism portion (601) being arranged between said contrast base
(50) and said second end portion (203; 203A) of cylinder;
said anchorage device (1; 1A) being suitable for taking on
a relatively compact rest configuration, wherein the penetrating and anchorage plates
(40) take on a first angular position wherein they are facing the cylinder side wall
(204; 204B, 204C); and
an anchorage configuration which is relatively unfolded with respect to the rest configuration,
wherein the penetrating and anchorage plates (40) take on a second angular position,
different from the first angular position;
wherein the anchorage device (1; 1A) comprises an abutment portion (205; 205A) and
the movement mechanism (60; 60A) comprises a stroke end element (602) which is integral
with said mechanism portion (601) and which is suitable for abutting against said
abutment portion (205; 205A) in order to stop the penetrating and anchorage plates
(40) in said anchorage configuration;
wherein the movement mechanism (60; 60A) comprises at least one distancing element
(610, 70) operatively connected to said mechanism portion (601) and arranged so as
to allow said mechanism portion (601) to move away from the second end portion (203;
203A) of cylinder when the hydraulic fluid (F) is input into the cylinder chamber
(201; 201A);
B) a step of inserting the anchorage device (1; 1A) connected to said tie rod (5)
into said perforating hole (H) and resting said contrast base (50) on the bottom (BW)
of said perforating hole (H);
C) a first step of inputting said hydraulic fluid (F) into said cylinder chamber (201;
201A) so as to move said mechanism portion (601) away from said second end portion
(203; 203A) of cylinder by means of said distancing element (610, 70), in order to
cause said penetrating and anchorage plates (40) to take on a third intermediate angular
position between said first and second angular position, the free ends (401) of penetration
of the penetrating and anchorage plates (40) pressing or partly penetrating the side
wall (SW) of the perforating hole in said third angular position;
and
D) a second step of inputting said hydraulic fluid (F) into said cylinder chamber
(201; 201A) so as to cause a translation of the cylinder body (20; 20A), said mechanism
portion (601) and the penetrating and anchorage plates (40) in the distancing direction
(X1) from the bottom (BW) of the perforating hole (H) so as to allow the penetrating
and anchorage plates (40) to further penetrate through the side wall (SW) of the perforating
hole (H) and so as to cause such plates (40) to take on said anchorage configuration.
7. An anchorage device (1E) for anchorage tie rods suitable for being inserted into a
perforating hole (H) made in a ground to allow anchoring an anchorage tie rod (5),
comprising:
- a hydraulic cylinder having a middle axis (Z1) and comprising a cylinder body (20E)
and a cylinder rod (30E) slidably mounted to the cylinder body (20E), the cylinder
body (20E) comprises a first cylinder chamber (201E) suitable for receiving a pressurized
hydraulic fluid (F), the cylinder rod (30E) comprises a first end portion (301E) of
rod received in the cylinder chamber (201E) and a second end portion (302E) of rod
opposite to the first end portion (301E) of rod, said cylinder body (20E) comprises
a first end portion (202E) of cylinder, an opposite second end portion (203E) of cylinder
suitable for being operatively crossed by the cylinder rod (30E) and a cylinder side
wall (204E) interposed between said first and second end portions (202E, 203E) of
cylinder;
- at least two penetrating and anchorage plates (40), each penetrating and anchorage
plate (40) having a free end portion (401) of penetration;
- a contrast base (50) associated with said second end portion (302E) of rod to allow
the anchorage device (1E) to be rested on a bottom (BW) of said hole (H);
- a movement mechanism (60E) operatively connected to the hydraulic cylinder for allowing
the movement of the penetrating and anchorage plates (40), said movement mechanism
(60E) comprising a mechanism portion (601E) to which the penetrating and anchorage
plates (40) are hinged and to which said anchorage tie rod (5) is suitable for being
connected, said mechanism portion (601E) being arranged facing said first end portion
(202E) of cylinder;
said anchorage device (1E) being suitable for taking on
a relatively compact rest configuration, wherein the penetrating and anchorage plates
(40) project from said mechanism portion (601E) on the side opposite to said contrast
base (50) and wherein they take on a first angular position wherein they are arranged
parallel or substantially parallel to the middle axis (Z1) of the hydraulic cylinder;
and
an anchorage configuration which is relatively unfolded with respect to the rest configuration,
wherein the penetrating and anchorage plates (40) take on a second angular position,
different from the first angular position;
wherein the movement mechanism (60E) comprises at least one distancing element (610E)
operatively connected to said mechanism portion (601E) and arranged so as to operatively
cross the first end portion (202E) of cylinder and to allow said mechanism portion
(601E) to move away from the first end portion (202E) of cylinder when the hydraulic
fluid (F) is input into the first cylinder chamber (201E) so as to allow the movement
of the penetrating and anchorage plates (40).
8. An anchorage device (1E) according to claim 7, wherein said at least one distancing
element comprises a hollow longitudinal member (610E) which is integral with said
mechanism portion (601E), said hollow longitudinal member (610E) being coaxial to
the cylinder rod (30E) and delimiting the first cylinder chamber (201E) on the side
opposite to the second end portion (203E) of cylinder, said hollow longitudinal member
(610E) being suitable for receiving a portion of cylinder rod (30E) comprising the
first end portion (301E) of rod when the anchorage device (1E) takes on the rest configuration.
9. An anchorage device (1E) according to claim 8, wherein said hollow longitudinal member
(610E) comprises a radially projecting longitudinal portion (611E) of member which
defines a movable wall of the first cylinder chamber (201E) .
10. An anchorage device (1) according to any one of claims 7 to 9, wherein said movement
mechanism (60E) comprises a plurality of connection linkages (620) interposed between
said first end portion (202E) of cylinder and said penetrating and anchorage plates
(40), wherein in said rest configuration, said penetrating and anchorage plates (40)
are arranged radially internal and said connection linkages (620) are arranged radially
external with respect to said penetrating and anchorage plates (40).
11. An anchorage device (1E) according to claim 10, wherein said movement mechanism (60E)
comprises a first and a second connection hinges (621, 622) arranged to connect each
connection linkage (620) to said first end portion (202E) of cylinder and to one of
said penetrating and anchorage plates (40) respectively, each penetrating and anchorage
plate (40) comprising a seat (402) suitable for at least partly receiving said second
connection hinge (622) so as to reduce or eliminate, in said rest configuration, the
radial projection of said second connection hinge (622) beyond the respective penetrating
and anchorage plate (40).
12. An anchorage device (1E) according to any one of claims 7 to 11, wherein the cylinder
body (20E) comprises a second cylinder chamber (207E) suitable for receiving said
pressurized hydraulic fluid (F), the second cylinder chamber being opposite to the
first cylinder chamber and being delimited by said distancing element (610E) on the
side opposite to the first end portion (202E) of cylinder, said distancing element
(610E) being arranged so as to allow said mechanism portion (601E) to move close to
the first end portion (202E) of cylinder when the hydraulic fluid (F) is input into
the second cylinder chamber (207E) so as to allow the movement of the penetrating
and anchorage plates (40) to cause the anchorage device (1E) to take on the rest configuration.
13. An anchorage device (1E) according to any one of claims 7 to 12, comprising a resistance
(70E) to the relative sliding between the cylinder body (20E) and the rod (30E), said
resistance (70E) to sliding being integral with the cylinder body (20E) and being
suitable for engaging or operatively contacting the cylinder rod (30E).
14. An assembly of parts (1E, 5, 15) comprising an anchorage tie rod (5), an anchorage
device (1E) as defined in any one of claims 7 to 13, and a head plate (15) for said
tie rod (5).
15. A process for anchoring anchorage tie rods, comprising:
A) a step of providing an anchorage device (1E) suitable for being inserted into a
perforating hole (H) made in a ground, and an anchorage tie rod (5) connected to the
anchorage device (1E), the anchorage device (1E) comprising:
- a hydraulic cylinder having a middle axis (Z1) and comprising a cylinder body (20E)
and a cylinder rod (30E) slidably mounted to the cylinder body (20E), the cylinder
body (20E) comprises a first cylinder chamber (201E) suitable for receiving a pressurized
hydraulic fluid (F), the cylinder rod (30E) comprises a first end portion (301E) of
rod received in the cylinder chamber (201E) and a second end portion (302E) of rod
opposite to the first end portion (301E) of rod, said cylinder body (20E) comprises
a first end portion (202E) of cylinder, an opposite second end portion (203E) of cylinder
suitable for being operatively crossed by the cylinder rod (30E) and a cylinder side
wall (204E) interposed between said first and second end portions (202E, 203E) of
cylinder;
- at least two penetrating and anchorage plates (40), each penetrating and anchorage
plate (40) having a free end portion (401) of penetration;
- a contrast base (50) associated with said second end portion (302E) of rod to allow
the anchorage device (1E) to be rested on a bottom (BW) of said hole (H);
- a movement mechanism (60E) operatively connected to the hydraulic cylinder for allowing
the movement of the penetrating and anchorage plates (40), said movement mechanism
(60E) comprising a mechanism portion (601E) to which the penetrating and anchorage
plates (40) are hinged and to which said anchorage tie rod (5) is suitable for being
connected, said mechanism portion (601E) being arranged facing said first end portion
(202E) of cylinder;
said anchorage device (1E) being suitable for taking on
a relatively compact rest configuration, wherein the penetrating and anchorage plates
(40) project from said mechanism portion (601E) on the side opposite to said contrast
base (50) and wherein they take on a first angular position wherein they are arranged
parallel or substantially parallel to the middle axis (Z1) of the hydraulic cylinder;
and
an anchorage configuration which is relatively unfolded with respect to the rest configuration,
wherein the penetrating and anchorage plates (40) take on a second angular position,
different from the first angular position;
wherein the movement mechanism (60E) comprises at least one distancing element (610E)
operatively connected to said mechanism portion (601E) and arranged so as to operatively
cross the first end portion (202E) of cylinder and to allow said mechanism portion
(601E) to move away from the first end portion (202E) of cylinder when the hydraulic
fluid (F) is input into the first cylinder chamber (201E) so as to allow the movement
of the penetrating and anchorage plates (40);
B) a step of inserting the anchorage device (1E) connected to said tie rod (5) into
a perforating hole (H) and resting said contrast base (50) on a bottom (BW) of said
perforating hole (H);
C) a first step of inputting said hydraulic fluid (F) into said first cylinder chamber
(201E) so as to move said mechanism portion (601E) away from said first end portion
(202E) of cylinder by means of said distancing element (610E), in order to cause said
penetrating and anchorage plates (40) to take on a third intermediate angular position
between said first and second angular position, the free ends (401) of penetration
of the penetrating and anchorage plates (40) pressing or partly penetrating a side
wall (SW) of the perforating hole (H) in said third angular position;
and
D) a second step of inputting said hydraulic fluid (F) into said first cylinder chamber
(201E) so as to cause a translation of the cylinder body (20E), said mechanism portion
(601E) and the penetrating and anchorage plates (40), in the distancing direction
(X1) from the bottom (BW) of the perforating hole (H) so as to allow the penetrating
and anchorage plates (40) to further penetrate through the side wall (SW) of the perforating
hole (H) and so as to cause such plates (40) to take on said anchorage configuration.