U.S. patent application number 13/062325 was filed with the patent office on 2011-06-30 for offshore station, foundation for an offshore station, and method for building an offshore station.
This patent application is currently assigned to MAX BOGL BAUUNTERNEHMUNG GMBH & CO. KG. Invention is credited to Stefan Bogl, Dieter Reichel.
Application Number | 20110158750 13/062325 |
Document ID | / |
Family ID | 41693581 |
Filed Date | 2011-06-30 |
United States Patent
Application |
20110158750 |
Kind Code |
A1 |
Reichel; Dieter ; et
al. |
June 30, 2011 |
Offshore Station, Foundation for an Offshore Station, and Method
for Building an Offshore Station
Abstract
An offshore station (1), in particular an offshore wind power
station, comprises a floatable foundation (2) that can be sunk by
flooding a hollow chamber, and a superstructure (6) on which
functional units (7, 8) of the station (1) are arranged. The
foundation (2) includes a bottom pale (3), a base (4) which is
disposed on the bottom plate (3) and projects from the water
surface (12) in the sunk state of the foundation (2) and on which
the superstructure (6) can be mounted, and a floodable floating
device (5) which surrounds the base (4) in the shape of a ring. In
a method for building an offshore station (1), in particular an
offshore wind power station, a floatable foundation (2) is
prefabricated in a harbor zone, is towed to a mounting location
after being prefabricated and is sunk, whereupon the station (1) is
completed with a superstructure (6) and functional units (7, 8) of
the station at the mounting location. In the harbor zone, a bottom
plate (3) of the foundation (2) is concreted, a base (4) of the
superstructure (6) preferably made of prefabricated concrete parts
(15) is mounted on the bottom plate (3), and a floodable floating
device (5) which surrounds the base (4) in the shape of a ring is
mounted on the bottom plate (3) and/or the base (4) once the base
(4) has been mounted.
Inventors: |
Reichel; Dieter; (Neumarkt,
DE) ; Bogl; Stefan; (Sengenthal, DE) |
Assignee: |
MAX BOGL BAUUNTERNEHMUNG GMBH &
CO. KG
Sengenthal
DE
|
Family ID: |
41693581 |
Appl. No.: |
13/062325 |
Filed: |
August 27, 2009 |
PCT Filed: |
August 27, 2009 |
PCT NO: |
PCT/EP09/61043 |
371 Date: |
March 4, 2011 |
Current U.S.
Class: |
405/205 |
Current CPC
Class: |
E02B 2017/0086 20130101;
F03D 13/22 20160501; E02B 2017/0091 20130101; Y02E 10/727 20130101;
E02B 2017/0065 20130101; E02D 27/42 20130101; F05B 2240/95
20130101; E02B 17/025 20130101; Y02E 10/72 20130101; E02D 27/425
20130101; E02B 2017/0078 20130101; E02B 17/02 20130101; F03D 13/10
20160501; E02B 17/0017 20130101 |
Class at
Publication: |
405/205 |
International
Class: |
E02D 27/52 20060101
E02D027/52 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 5, 2008 |
DE |
10 2008 041 849.8 |
Claims
1. Foundation (2) of an offshore station (1), especially an
offshore wind power station that can float and can be sunk by
flooding a hollow space characterized in that the foundation (2)
encompasses a bottom slab (3) and, arranged on the bottom slab (3),
a base (4), which juts out from the water surface (12) when the
foundation (2) has been sunk and on which a superstructure (6) of
the offshore station can be mounted, as well as a preferentially
annular floating body (5) constructed around the base (4) that can
be flooded.
2-32. (canceled)
Description
[0001] The invention refers to an offshore station, especially an
offshore wind power station that comprises a floatable foundation
that can be sunk by flooding a hollow chamber and a superstructure
on which functional units, especially a wind power station gondola
and rotor, are arranged. Furthermore, the invention refers to a
foundation of an offshore station and a method for building an
offshore station, especially an offshore wind power station in
which a floatable foundation is prefabricated in a harbor zone,
transported after completion to a mounting location, and sunk
there. Subsequently, the station with the superstructure and
functional units, especially a gondola and a rotor of a wind power
station, is completed at the mounting location.
[0002] Various methods for building offshore wind power stations
are known. In some of them, steel caissons or reinforced concrete
built on land are used for different types of seafloors. The
caisson foundations can float and are transported to the mounting
places with loading cranes. Once in their mounting positions, the
caissons are filled with sand, pebbles or other dense materials so
they can have the needed weight. In this case, the wind power
station itself is generally fully mounted in a nearby port and
transported to the mounting location, where the towers of the wind
power station are raised with floating cranes and mounted onto the
foundation. The use of floating cranes is relatively expensive and
the transportation and erection of the tower depend strongly on
weather conditions.
[0003] DE 10 2007 002 314 A1 envisages a foundation for an offshore
station prefabricated on land or, if applicable, a fully
prefabricated wind power station hung with ropes in an especially
equipped transportation ship so it can be attached to it. The
foundation includes an immersion body whose buoyancy can be
increased so the special ship can tow the foundation to the
mounting location, where it is sunk by loosening the suspension.
The transportation ship, in turn, detaches from the foundation so
it can move away from the mounting location. The specially built
ship can be designed merely as a swimming body without own
propulsion and must then be brought to the mounting location by
another ship. In this scenario, the foundation and the station
itself cannot float.
[0004] DE 102 06 585 A1 and DE 2 359 540 envisage the building of a
floatable foundation partially on land or in a harbor zone,
bringing it to the mounting location to be sunk there. In each
case, the floatable foundation is sunk by flooding and, if need be,
anchored to the seafloor by flushing. In DE 2 359 540, a likewise
floatable tower superstructure (prefabricated on land) is
positioned on top of this foundation float. The tower
superstructure is towed in horizontal position to the mounting
location, raised there through controlled flooding (with the help
of special lifting devices if need be) and lowered slowly to a
corresponding foundation recess. Only then can a superstructure be
mounted on the tower, which is designed for oil extraction in DE 2
359 540. The superstructure is also prefabricated on land or in a
harbor, towed to the mounting location and mounted there onto the
tower.
[0005] DE 102 06 585 A1 describes a tower foundation consisting of
numerous cylinder-shaped chambers that can be individually flooded.
The tower foundation is prefabricated on land and towed in resting
position to its mounting location, where the chambers are flooded
in a controlled way, the tower foundation raised to the vertical
position, and sunk. However, the tower foundation juts out from the
water surface for receiving the superstructure of the offshore
station. Since the sinking process greatly affects floating
stability, an external stabilization is provided for.
[0006] The task of this invention is to suggest an offshore station
with a floatable foundation and a corresponding, easily built
foundation that can be transported to the mounting location.
Furthermore, a method for achieving this task will also be
suggested.
[0007] The task is solved with the characteristics of the
independent claims.
[0008] An offshore station, especially an offshore wind power
station, encompasses a floatable foundation that can be sunk by
flooding a hollow space and a superstructure on which the station's
functional units are arranged. The station can be an offshore wind
power station on whose tower the foundation is mounted. In turn,
the gondola and rotor are mounted as functional units on the tower.
According to the invention, the foundation includes a bottom slab
and a base arranged on it. When the foundation has been sunk, the
base juts out from the water surface so that the superstructure can
be easily mounted on it above the surface. Furthermore, the
foundation includes a preferably ring-shaped floating body
constructed around the base that can be flooded. Owing to the
preferably ring-shaped floating body, a favorable center of gravity
in the foundation with respect to the base can be achieved in spite
of the latter's height. Thus, the foundation is particularly stable
when floating and can be towed to the mounting location in the
position that will be installed. The favorable center of gravity of
the foundation can also allow it to be sunk at the mounting
location without external stabilization. In this case, the base of
the station can also be directly attached to the bottom slab
already when the foundation is being prefabricated, thus doing away
with the hook-up work at the mounting location.
[0009] A floatable foundation is prefabricated in a harbor area in
an offshore station erection. After its completion, the floatable
foundation is towed to a mounting location to be sunk there.
Afterwards, the station is completed at the mounting location by
adding a superstructure, which can be the tower of a wind power
station and its functional units like a gondola and rotor, for
example. According to the invention, a bottom slab is covered with
concrete in the harbor area. Then, the base of the superstructure
is mounted on it, and after the base mounting has been completed,
an annular-shaped floating body built around the base is mounted on
the bottom slab and/or base. Thus, the foundation encompasses the
station's entire support, which extends barely above the water
surface. The method according to the invention allows the entire
foundation with the base to be already prefabricated onshore or on
a floating pontoon in the harbor area. Likewise, the foundation can
be finished in a dry dock and then dropped into the water.
[0010] The base is preferably built in the harbor area from
concrete components that allow the foundation to be very easily and
quickly constructed to avoid long and costly harbor lay times. The
concrete components can be economically prefabricated and
transported to the harbor without special transportation but a base
already pre-mounted on land can be mounted on the bottom slab, to
finish the work done on the bottom slab very quickly. The base can
also be built up of concrete components.
[0011] In this case, it is preferable for the floating body to be
made primarily of pre-assembled units, if possible of concrete
components, because then all foundation components can be
prefabricated economically on land and quickly mounted in the
harbor area. This can greatly reduce the needed mounting time in
the harbor area.
[0012] Here, it is preferable if at least one external ring wall of
the floating body is constructed on the bottom slab applying the
prefabricating method. In principle, however, the outer ring wall
could also be constructed in the cast-in-situ concrete. In this
case, it is very advantageous if the ring wall is mounted directly
on the bottom slab so the latter is simultaneously the bottom of
the floating body. With this method, the foundation can be built up
very easily.
[0013] A floating body cover slab can also be mounted in pre-cast
or cast-in-situ concrete on the outer ring wall. If the cover slab
is made with the pre-cast construction method, it is advantageous
for the prefabricated parts to have a segmented ring shape so they
can be easily arranged around the base. The individual concrete
components of the ring wall and the base can also have a segmented
ring shape for convenient mounting and a stable construction can be
built on them. However, the concrete components of the base can
also have a full ring shape. It is also possible to make the
individual concrete components as rectangular, flat plates, mounted
in bracing position against one another to create a ring wall. In
any case, an advantageous and fast mounting is possible by
constructing the foundation out of concrete components in the
harbor area. These components can be cheaply prefabricated outside
the harbor and easily assembled together to create a floating and
stable foundation. As the base has already been integrated into the
foundation, difficult construction work that would have to be
performed after sinking the foundation is no longer needed.
Nonetheless, owing to its floating and stable construction, the
foundation can be easily transported to the mounting location.
[0014] So the floating body can be stabilized during sinking, it is
advantageous if it is subdivided by partition walls that create
ring-segmented chambers that can be individually flooded.
[0015] According to another execution of the invention, it is also
advantageous for the floating body to especially have the form of
several closed annular segmented containers. The containers can
also be flooded in a controlled way for allowing sinking and be
filled with filling material, if need be. Once the foundation has
been sunk, they can be easily detached and reused for erecting
other stations.
[0016] Another execution of the invention envisages the floating
body to be made of several closed, barrel-shaped containers
annularly arranged around the base. The containers can be made
quite economically and reused for other stations regardless of the
base dimensions.
[0017] Furthermore, the floating body can also consist of several
floatable buoyancy bodies, preferentially made of concrete
components. Even these can be executed so they can be detached.
[0018] The floating body and the steel or concrete containers can
be executed so they are only partly detachable so a section of the
floating body or the container can be ballasted and another section
reused. For construction reasons, sections of the floating body can
also remain in the sunk foundation or used for creating a
biotope.
[0019] After completing the foundation with the base and the
floating body, the foundation in mounting position can be towed
from the harbor area in a floating pontoon, for example, launched,
then towed to the mounting location and finally sunk by flooding
the floating body in mounting position. In this case, a raising or
external stabilization with floating cranes or the like is not
necessary. The foundation can also, however, be constructed
entirely on land or in a dry dock and then launched.
[0020] Preferably, the foundation is sunk to the seafloor by
flooding the floating body. To sink the foundation, it is also
advantageous if an interior space of the wind power station base
can be flooded.
[0021] Besides, it can be advantageous if an interior space of the
floating body and/or base can be filled with filling material to
increase the weight of the foundation.
[0022] However, instead of sinking the structure to the seafloor
and depend on the configuration of the soil, it can also be
advantageous to sink the floatable foundation by flooding the
floating body on piles because they allow a positioning on the
floor even with bad soils. In addition, a favorable scour
protection can be simultaneously achieved in this case because
water can flow through the piles under the foundation. Here, it is
advantageous to build three piles in the floor with mainly the
exact height. To position the foundation on the piles, it can be
tensioned against the piles with a fastening device and adjusted,
if need be. Afterwards, a space between the piles and an underside
of the foundation is preferably filled with concrete.
[0023] According to a favorable embodiment of the invention, the
foundation's floating body is removed after sinking. In this case,
the foundation has a heavy bottom slab for sufficient weight that
needs no sand or pebble filling. The floating body can be easily
detached if it consists of several closed containers.
[0024] Besides, it is advantageous for the bottom slab to have an
annular contact area because the weight distribution below the
surface would then be especially easy to carry out. If the bottom
slab is conical, a sufficient weight of the bottom slab can
nevertheless be achieved.
[0025] It is also advantageous if the station is built
preferentially from annularly segmented concrete components, as
these can be economically prefabricated in large numbers and easily
transported to the construction site.
[0026] According to another advantageous further development of the
invention, the concrete components of the structure and/or base are
clamped dry against one another and/or the bottom slab. In this
case, a sealing with epoxy is not necessary. It is better if the
contact points of the concrete components are ground over before
clamping so the concrete components can lie flat on top of each
other. However, sealing can nonetheless take place depending on how
the concrete components are executed.
[0027] It is furthermore advantageous if the contact points have at
least a partial shear interlocking or profiling. In addition to
absorbing forces, the shear interlocking can also serve for putting
the concrete components together with precision.
[0028] It is furthermore advantageous for the base to have an
annular fastening flange for fastening a steel tower. The flange
can be prefabricated on land and mounted whole on the base.
[0029] It is also advantageous if after sinking the foundation an
interior space of the base and/or the floating body is pumped dry.
The interior space of at least the base can thus be used for
storage purposes or for putting the station's technical parts.
[0030] Likewise, it can also be advantageous, however, to fill the
interior space of the base and/or floating body with filling
material such as sand or pebbles after sinking.
[0031] Other advantages of the invention are described with the
help of the embodiments shown in the following figures, which
show:
[0032] FIG. 1 An overview of the off-shore station according to the
invention,
[0033] FIG. 2 A section drawing of the foundation according to the
invention,
[0034] FIG. 3 Another execution of the foundation,
[0035] FIG. 4 A top view of a foundation of an offshore station
according to the invention,
[0036] FIG. 5: A perspective drawing of a container as part of a
floating body, and
[0037] FIG. 6: A perspective drawing of a foundation according to
the invention with barrel-shaped containers.
[0038] FIG. 1 shows a schematic diagram of an offshore station 1
according to the invention in a partial section. The station 1 at
hand is executed as a wind power station on a foundation 2
according to the invention, but another structure or station 1 like
a drilling platform or something similar can also be built up on
the foundation instead of a wind power station.
[0039] The wind power station 1 encompasses a floatable foundation
1 that in this drawing includes a bottom slab 3, a base 4 and a
floating body 5. Furthermore, the wind power station 1 includes a
tower 6, a machine gondola 7 and a rotor 8. Instead of the tower 6
of the wind power station 1, another superstructure 6 with the
respective functional units can also be built up on the foundation,
of course.
[0040] The floatable foundation 2, shown in a section drawing in
FIG. 2 and an alternate execution of it in a perspective drawing in
FIG. 3, encompasses according to the invention a stable bottom slab
3 made preferentially of concrete and has a conventional
reinforcement. In this case, the bottom slab 3 is round and has an
approximate diameter of 30 to 35 meters.
[0041] The underside of the bottom slab can have a recess 14 so
that the bottom slab 3 has an annular contact surface as can be
seen in FIG. 2. In addition, the bottom slab 3 can have a slightly
conical shape. As a result of this, a favorable load-bearing
capacity can be achieved in the bed of the seafloor 13 if the
bottom slab 3 has a considerable weight. In this case, the bottom
slab can be made of in-situ concrete in land and afterwards taken
on a floating pontoon to a small inner harbor or preferably placed
in in-situ concrete on a floating pontoon. Afterwards, the base 4
is braced on the bottom slab 3 with bracing elements on the
floating pontoon located in the inner harbor area. In this
scenario, the base 4 can already be prefabricated on land and
braced only against the bottom slab 3 in the inner harbor area or
it can be built from concrete components 15 on the floating pontoon
located in the inner harbor area.
[0042] The individual concrete components 15 of the base consist
here of individual annular segments, and each segment in turn can
consist of several ring segments 16, as shown in FIG. 3. To brace
the base 4 on the bottom slab 3, grooves for the bracing elements
can be arranged in a known way in the wall of the concrete
components 15 or the annular segments 16. Instead of guiding the
pre-stressing elements in the wall, it is also possible, however,
to arrange the pre-stressing elements outside of the wall in the
interior space 17 of the base or outside of the base 4. In this
case, the pre-stressing elements running along the interior space
17 of the base 4 can be arranged economically and at the same time
protected from corrosion. Likewise, the pre-stressing elements led
in channels in a known way can be tightly pressed in with a filling
material after bracing to achieve protection against corrosion.
Likewise, the annular segments 16 are braced with clamping devices
and afterwards pressed in if need be. To prevent the grouting agent
from seeping out, sealing agents can also be arranged in this case
if necessary.
[0043] After mounting the base 4 on the bottom slab 3, the floating
body 5 of the foundation 2 is mounted on the floating pontoon (not
shown). According to an initial execution of the invention, the
floating body 5 consists likewise mainly of concrete components 19
that are also prefabricated and can be quickly mounted in the inner
harbor area. In this case, the floating body 5 is constructed in an
annular shape around the base 4 on the bottom slab. As a result of
this, it is on the one hand possible to anchor the base 4 onto the
bottom slab 3 independently from the floating body 5 and, if
desired, to remove the floating body 5 after sinking the foundation
2. If necessary, however, the floating body can also be filled with
filling material to achieve sufficient weight in the foundation to
be sunk.
[0044] However, the annular geometry of the floating body 5, in
particular, can achieve a favorable center of gravity in the
foundation 2. Thus, it is possible to finish the foundation 2 with
the floating body 5 and the base 4 in full mounting position
already in the harbor area, splash it down, tow it to the mounting
location and then sink it in mounting position too. Thanks to the
design according to the invention, the foundation is particularly
stable when it floats and can also be easily constructed from
prefabricated parts for fast mounting in the harbor area.
[0045] The concrete components 19 of the floating body can in this
case be arranged similarly to those of the base 4 as annular
segments, as shown in FIG. 2. However, as an alternative shown in
FIG. 3, the concrete components 19 can also be made of individual
rectangular plates. In this case, the concrete components 19 of the
floating body are also braced against one another and against the
bottom slab 3 with suitable clamping devices. According to another
alternative (not shown), it is also possible to cast the outer ring
wall 9 of the floating body 5 in in-situ concrete on the bottom
slab 3.
[0046] After mounting the ring wall 9 of the floating body 5, the
cover slab 20 of the floating body 5 can be mounted onto the ring
wall 9. In this case, the cover slab 20 can be a continuously
annular cover slab 20, as the top view of FIG. 4 shows, or executed
as an element cover, as can be seen in FIG. 3. In this case, the
cover slab 20 can consist of individual annularly segmented
prefabricated parts. A combination of prefabricated and in-situ
cast concrete construction is also possible. As especially apparent
in the sectional drawing of FIG. 2, the floating body here is built
up in such a way that the bottom slab 3 is at the same time the
bottom of the floating body 5.
[0047] FIG. 4 shows a top view of a foundation of a wind power
station according to the invention, in which case the cover slab 20
has been executed annularly in in-situ concrete. Broken lines
represent the wall sections of the base 4 that widen downward. As
FIG. 4 also shows, individual bulkhead walls 21 can be arranged in
the floating body 5 for stabilizing the floating body 5. In this
case, the bulkhead walls 21 can also be prefabricated as concrete
components. The bulkhead walls 21 are preferentially arranged in
such a way that individual annularly segmented chambers 22 are the
result. On the one hand, the bulkhead walls 21 increase the
stability of the floating body 5 and, on the other hand, facilitate
a selective flooding at the mounting location so the foundation 2
can be sunk in mounting position without the risk of tilting. For
this purpose, each chamber 22 has at least one opening or the
corresponding valves (not shown) to make a selected flooding
possible.
[0048] FIG. 5 shows a perspective drawing of an alternative design
of the floating body 5. Here, the floating body 5 is made from
several preferentially annularly segmented containers 23 arranged
around the base 4 and fastened to the bottom slab 3 and/or the base
4. In this case, the floating body 5 can be very easily loosened
and then detached from the foundation slab after sinking the
foundation 2. For this, the bottom slab 3 is executed so heavily
that it still weighs enough after the flooded floating body 5 has
been removed. The execution with individual containers 23 is
therefore especially suitable for smaller wind power stations 1.
The containers 23 also have one or several openings or valves for
selective flooding. For dismounting the floating body 5 or the
container 23 it is advantageous if the interior space of the
container can be pumped dry to increase buoyancy and transport the
containers 23 to the water surface. The containers 23 can in this
case be reused in other wind power stations 1 to be erected.
Preferably, the containers 23 are executed as steel containers, but
floatable containers or buoyancy elements made of concrete or
concrete components can also be similarly used. Since costly
artificial biotopes and reefs are very often constructed, it is
also conceivable to leave the floating body 5 on the foundation
after sinking and to open it in various places to create a biotope
through water exchange. Depending on location, however, the
containers of the floating body can also remain on the foundation
that has been sunk and be used for ballast purposes in their final
state.
[0049] FIG. 6 shows another execution of the invention in which the
floating body 5 consists of several barrel-shaped containers 23.
These barrel-shaped containers 23 can be made in an especially
economical way because they can be designed independently from the
dimensions of the foundation 2 and the base 4. The containers 23
are also annularly arranged around the base 4 to create the
floating body 5. Even in this execution, the foundation 2 has good
floating stability. As described above (FIG. 5), the containers 23
can be selectively flooded to have better control of the sinking
process and prevent a tilting of the foundation 2. Preferably, the
sinking process is initiated by flooding the containers 23 and the
interior of the base 4 first. Afterwards, only the containers
continue to be flooded to sink the foundation 2 fully and uniformly
to the sea floor 13. After the foundation 2 has been sunk, the
containers 23 can be dismounted and reused for other stations 1. To
achieve an adaptation to different dimensions of stations 1, the
number of containers 23 can be correspondingly reduced or
increased.
[0050] Furthermore, according to the execution shown in FIG. 6, the
individual containers 23 can be made of steel, concrete or concrete
components or a combination thereof. Thus, the lower ring segments
of the barrel-shaped containers 23 can be made of concrete, for
example, and after sinking the foundation 2 remain at the mounting
location, while detachable steel containers are arranged above the
ring segments.
[0051] Depending on the design of the station 1 and the bottom slab
3, the floating bodies can also be filled with a filling material,
however, and remain on the bottom slab 3 or used for creating a
biotope.
[0052] After completion of the foundation 2 with the base 4 and the
floating body 5 on a floating pontoon or something similar in the
inner harbor area, the floating pontoon is finally towed to deeper
waters and unloaded so the foundation 2 floats by itself in
mounting position. The depth of the foundation 2 in the floating
state is preferably 6 to 10 meters here, so that drainage near the
harbor or in the inner harbor area is possible. Afterwards, the
foundation 2 is towed to the mounting location, where it is sunk to
the sea floor 13 by selectively flooding the chambers 22 or
containers 23, as shown in FIG. 2.
[0053] The preparation of the sea bed is done conventionally here
by stone filling but other scour protection measures are also
conceivable, however. Especially in an execution in which the
floating body 5 is removed after sinking the foundation 2, scour
protection must be heeded. Thus, for example, when the floating
bodies are dismounted, the bottom slab protruding from the
remaining tower can be equipped with guiding devices for the
current. These guiding devices can naturally be placed on top
afterwards too or mounted around it so that as a result of this a
washout of the bottom slab is hindered or at least restricted. This
is especially a good idea in the North Sea.
[0054] Optionally, however, the foundation 2 (as shown in FIG. 1)
can be sunk on piles 24 if bottom conditions make this necessary.
The piles 24 can support the foundation 2 at the height of the sea
bottom or also do it with a predetermined distance above it. To
achieve this, preferably three piles of roughly the same height are
driven into the sea floor 13. In this case, the foundation 2 is
braced at first to the piles 24 to achieve the correct orientation.
With the help of the clamping devices not shown here, a fine
adjustment takes place and afterwards the space 25 between the
piles 24 and the foundation 2 is cast. Finally, the foundation 2 or
the floating body 5 is fully flooded.
[0055] In another embodiment of the invention, the floating body 5
can be flooded first and sunk on the piles 24 for the fine
adjustment. In order to connect the piles 24 with the foundation 2
and to achieve an orientation at precisely the same level, the
floating body 5 can be lifted a bit by partially pumping the water
out of the floating body 5 and a space 25 between the piles 24 and
the underside of the foundation 2 be filled with a casting
compound. If in this design the bottom slab 3 does not lie directly
on the subsurface, then the water can flow through the piles 24
under the bottom slab so no additional scour protection measures
are needed. After the foundation has been sunk, the floating body 5
and the corresponding containers or buoyancy bodies can be
dismounted if need be.
[0056] If the foundation 2 is directly placed on top of the sea
bottom in case of a suitable subsurface (i.e. without piles 24),
then it is advantageous if the foundation 2 or the bottom slab is
at least partially, preferentially but fully undergrouted with
undercast mortar, for example. In this process, the foundation is
straightened with respect to the sea floor and finely adjusted and
fixed in place by the bottom grouting.
[0057] After the foundation has been sunk at the mounting location,
the wind power station 1 is finally completed with the tower 6, the
machine gondola 7 and the rotor 8 at the mounting location. In this
case, a tower 6 made of concrete components 27 or a steel tower can
be used.
[0058] The concrete components 15, 16, 27 of the base 4 or also of
a tower 6 of the wind power station 1, which like the base 4 can be
built up of prefabricated parts 15 or annular segments 16 in the
manner described above, are braced preferentially dry (i.e. without
using a sealing or composite material such as epoxy) on top of each
other. In this case, the concrete components 15, 16, 27 can also be
ground before bracing to achieve a smooth supporting surface and a
good connection with the correspondingly adjacent prefabricated
part 15, 27. The contact points of the prefabricated parts 15, 27
can have smooth surfaces or also a shear interlocking. They can
serve not only for absorbing forces but also for the precisely
positioned arrangement of the prefabricated parts 15, 27 with
respect to one another. Likewise, the prefabricated parts 19 of the
floating body 5 can also be mounted in the manner described
above.
[0059] Finally, a fastening flange 18 (as shown in FIG. 3) can be
arranged on the base 4 to arrange, if need be, a pre-manufactured
steel tower 6 on the base 4 at the mounting location. The flange 18
can in this case be executed as a threaded flange or also as a
clamping device flange. For this purpose, the fastening flange 18
is ring-shaped and has mainly a U- or L-shaped cross section. The
steel tower can be pre-manufactured in this case or be put together
not until it is at the location from individual (for example,
annular) elements with the corresponding flanges.
[0060] If, on the other hand, the tower 6 is built up from concrete
components 27 then it is braced like the base 4 against the bottom
slab 3 and/or against the base 4. In this case, the tensioning
elements can run in cladding tubes of the walls of the concrete
components 15, 27 or arranged outside, in which case they run
preferentially in the interior space of the base 4 or of the tower
6. Furthermore, it is also possible to have anchors at various
heights, both on the base 4 and the tower 6, and to brace the tower
6 and the base 4 only over a partial length. This facilitates
subsequent tensioning. Such anchors can also be placed inside or
outside. It is additionally also possible to pull the tensioning
elements that run in the interior space 17 of the base 4 or of the
tower 6 towards the exterior on a coupling spot to facilitate the
tensioning process.
[0061] It could also be possible to pump dry at least the interior
space 17 of the base 4 for use as instrument or storage room. In
this case, it may be advantageous to also empty the interior space
26 of the floating body 5 and to fill it with sand, pebbles or
another dense filling material in order to provide the foundation 2
with the needed weight. Depending on soil composition, it can also
be advantageous to fill the interior space 17 of the base 4 with a
filling material too. On the other hand, the ring room 26 of the
floating body can also be partially pumped dry, at least when it is
subdivided into chambers 22, for use as storage too.
[0062] The invention is not restricted to the embodiments shown.
For example, the foundation 2 can also naturally have a
non-circular design. Consequently, the floating body 5 with the
ring-shaped design must not have a circular ring shape either, but
can also have another closed shape, for example an oval. The
floating body cannot be ring-shaped or be executed as an open ring
if, as a result of this, a stable position of the foundation can
nonetheless be ensured. Variations and combinations within the
framework of the patent claims also fall under the invention.
* * * * *