Abstract:
A wind power plant tower segment is provided. The tower segment is designed as a jacket segment and comprises a reinforced concrete body, comprising two faces for attaching to faces of at least one further tower segment. In the region of each face, at least one connecting body is introduced in the reinforced concrete body and anchored therein for connecting to a connecting body of an adjoining tower segment. The connecting body comprises a fastening wall that is disposed substantially parallel to the respective face for absorbing a tensile load that is directed transversely to the face and transversely to the fastening wall. A wind power installation pylon having a plurality of such pylon segments, a wind power installation having a corresponding pylon, and a process for the production of a plurality of pylon segments is also provided.

Description:
BACKGROUND 
     1. Technical Field 
     The present disclosure concerns a wind power installation pylon segment and a wind power installation pylon having a plurality of such pylon segments and a wind power installation having a corresponding pylon. The disclosure further concerns a process for the production of a plurality of such pylon segments. 
     2. Description of the Related Art 
     Nowadays a modern wind power installation usually includes a foundation on which is arranged a wind power installation pylon carrying a pod in which there is accommodated a generator, the rotor of which is rotated by an aerodynamic rotor for energy generation with a suitable wind. Pylons of such wind power installations can be of heights of over 100 m. Besides steel pylons, concrete pylons consisting of steel reinforced concrete and/or prestressed concrete are frequently used. In that respect the term concrete pylon is used to mean that it is predominantly made from concrete. An upper portion can frequently be made from steel. 
     Such a pylon is substantially of a tubular shape and usually differs from a strictly cylindrical shape in that it decreases in diameter from the foundation to the pod. Such a concrete pylon is usually constructed from a plurality of precast concrete parts. In a vertical direction such a pylon has a plurality of mutually superposed pylon portions which are usually fixedly braced together in the vertical direction by bracing cables. Each of those pylon portions or at least pylon portions from the lower region of the concrete pylon are composed of outer peripheral casing segments. For example a pylon portion can be composed of two half-shells which basically each form a 180 degrees segment of the pylon portion. Those pylon portions are mostly prefabricated industrially in the form of precast concrete parts and are assembled and joined together on site when constructing the pylon. The need to subdivide the pylon portions into a plurality of segments is usually due to necessary transport of the components from their location of manufacture to the location at which the wind power installation is erected. 
     Pylon segments of a pylon portion, which can also be referred to as the pylon section, are usually assembled on site at perpendicular joint edges. Portions of the reinforcement project out at those joint edges so that here the segments can be connected together by means of a locking bar. The remaining vertical gap is then mortared. 
     A disadvantage in this respect is that a quite large amount of manual work is required for connecting the pylon segments together. The mortar filling also hides the danger of corrosion of the reinforcement portions in that region, particularly if the mortaring operation is not effected correctly or is defective. In that respect, mistakes or defects can occur even when the operation is implemented carefully. Such defects can be, for example, enclosed water and air bubbles or capillaries leading outwardly from the reinforcement. 
     In addition, the positional accuracy that can be achieved with such pylon segments relative to each other is limited and is usually in the range of +10 mm. Furthermore the mortaring operation can be problematical in winter at low temperatures. 
     BRIEF SUMMARY 
     Embodiments of the present invention overcome or reduce at least one of the aforementioned problems. In particular, embodiments of the invention simplify the operation of connecting a plurality of pylon segments together and/or improve in respect of positional accuracy and/or reliability and/or durability. 
     According to at least one embodiment of the invention, there is proposed a pylon segment. Such a pylon segment is in the form of an outer peripheral casing segment and is prepared for being assembled to at least one further such or similar pylon segment to provide a pylon portion, which is also referred to as a pylon section. In that respect, the term pylon portion is used to denote a tubular portion which is closed in the peripheral direction. A pylon has a plurality of mutually superposed pylon portions. 
     The pylon segment has a steel reinforced concrete body and thus a concrete body provided with a reinforcement. For assembly to at least one further pylon segment there are provided two joints for attachment to joints of at least one further, in particular similar or identical pylon segment arranged in the same plane in order thereby be able to manufacture a pylon portion. Such a joint is a surface and is substantially or at a maximum of a length in accordance with the height of the pylon segment and is of a width in accordance with the thickness of the pylon segment, that is to say the wall thickness of the pylon segment. In other words, such a joint corresponds to a sectional surface of a perpendicular section through the pylon segment, in which respect the joint can possibly be somewhat smaller and in particular somewhat narrower. 
     At least one connecting body is let into the region of each joint and anchored therein. Such a connecting body is provided and adapted to be connected to a further connecting body of the adjacent pylon segment. In that case, the two connecting bodies can be in contact with each other or there is at least a little different material therebetween, in particular concrete. The connecting body has a fixing wall arranged substantially parallel to the respective joint, for carrying a tensile loading directed transversely relative to the joint and the fixing wall. Here a fixed connection can be made between the connecting body and a connecting body of a further pylon segment. That provides for a firm connection of the aforementioned pylon segments with each other, by virtue of the connecting body being anchored in the steel reinforced concrete body. In that respect, preferably a plurality of connecting bodies are arranged along a joint, in particular at equal spacings. 
     According to at least some embodiments of the invention, therefore two pylon segments can be fixedly connected together in joint-on-joint relationship. A high degree of accuracy is achieved with that connection, such accuracy being substantially determined by the production accuracy of the pylon segments. 
     Preferably the pylon segment is a precast concrete part. Such a precast concrete part can be industrially prefabricated, whereby it is possible to achieve a high quality and thus strength for the steel reinforced concrete body. A high degree of accuracy and quality for the joints can also be achieved. 
     Preferably the connecting body is in the form of a connecting box or steel recess. The terms connecting box and steel recess are used synonymously hereinafter. 
     The connecting box has preferably a plurality of and in particular three side walls adjoining the fixing wall in order thereby to form a cavity, in particular a recess. The side walls and the fixing wall are in that case fixedly connected together. In that arrangement the connecting body also has an open side accessible from the outside, wherein the connecting body is fixedly connected to reinforcing bars which are let into the steel reinforced concrete body so that the connecting body is thereby anchored in the steel reinforced concrete body. The cavity is accessible through the open side accessible from the exterior. In other words it is possible to gain access to the cavity from outside the pylon segment. In that respect, the pylon segment is preferably so constructed that it is possible admittedly to gain access to the cavity from outside the pylon segment, but from within the interior of a wind power installation pylon which has been constructed or which is to be constructed. That outwardly open cavity or the outwardly open recess would accordingly not be exposed to weathering influences at the exterior of the wind power installation or at any event to fewer weathering influences. 
     In an embodiment there is proposed a pylon segment which is characterized in that a first of the side walls is opposite the open side and at least one reinforcing bar connected to the first side wall is inclined relative to at least one reinforcing bar connected to one of the other side walls through an angle of inclination, wherein the angle of inclination is preferably in the range of about 2 to 8 degrees, further preferably in the range of about 3 to 5 degrees and in particular is about 4 degrees. 
     By virtue of the provision of angles of inclination of the reinforcing bars relative to each other and thus the fixing of the reinforcing bars to the connecting body at different angles of inclination, forces can be diverted in a correspondingly different direction. In that way it is possible to take account of the tubular structure of the wind power installation pylon and thus the curved shape of the pylon segment. The angle of inclination can be in the range of 2 to 8 degrees, which can depend on particular on the pylon diameter in the region of the pylon segment in question. The smaller the diameter, the correspondingly greater can be the angle of inclination. Angles of inclination of 3 to 5 degrees, in particular about 4 degrees, are advantageous for usual diameters. 
     Preferably the connecting body is so arranged in the steel reinforced concrete body and in particular is concreted therein that it is accessible from the exterior. In particular that also permits access to the connection implemented by way of the connecting body, to another connecting body of an adjoining segment. In contrast the reinforcing bars are so arranged and connected to the connecting body that they are completely enclosed in the pylon segment and are thus inaccessible from the exterior. That can provide corrosion protection for the reinforcing bars in a long term. In that arrangement, the reinforcing bars are substantially enclosed by concrete and at the connecting location in relation to the connecting body they are enclosed by the connecting body or screened off relative to the exterior. 
     A preferred fixing of the reinforcing bars to the connecting body is effected by means of welding. That makes it possible to achieve a permanent and strong connection, by way of which in addition high forces can be transmitted. 
     A further desirable configuration proposes that the fixing wall terminates approximately with the joint and/or the fixing wall has at least one fixing opening for passing therethrough at least one tensioning means, in particular a screw, in order by said tensioning means to transmit a tensile loading from a further pylon segment to the fixing wall. 
     The statement that the fixing wall terminates approximately with the joint signifies that the connecting body is let into the steel reinforced concrete body in such a way that an outside surface of the connecting wall forms a part of the joint, that is to say the contact surface with an adjacent segment. That makes it possible to provide for direct contact of the connecting bodies with each other when two segments are fitted together at their joint and the connecting bodies are correspondingly arranged at both joints. In a corresponding fashion, it is also possible to provide that the connecting bodies, and thus the segments, are fixedly connected in a simple fashion. The two segments are thus directly fixed in joint-to-joint relationship so that it is possible substantially or completely to remove the need for mortar filling. An elastic sealing material can be provided in some embodiments. 
     Reinforcing bars can also be connected to the connecting body in such a way that they are not accessible from the exterior, for the situation where the fixing wall terminates approximately with the joint. In other words the reinforcing bars can be fixed to the connecting body in somewhat set-back relationship with the joint. 
     The provision of at least one fixing opening in the fixing wall for passing therethrough a tensioning means such as a screw makes it easily possible to provide a fixing option and ultimately also a bracing option for two connecting bodies in relation to each other. Thus, such a screw or threaded rod can connect two adjacent connecting bodies of two adjacent pylon segments. If the connecting body is in the form of a connecting box with a cavity or recess which is accessible from the exterior, the fixing operation and in particular the screw-tightening operation can be effected in relation to both connecting bodies which are to be connected together, in that cavity or recess. 
     That makes it possible to achieve a strong and also highly precise joint-to-joint connection between two segments because the operation of making the fixed connection or tightening the connection is not effected in the region of the contact surface or join, but in the recesses or cavities which are accessible from the exterior. In order finally to additionally counteract corrosion and in particular also corrosion of the connecting bodies, it is proposed that after conclusion of the fixed connection, a rubber sheathing is provided for the cavities or recesses. 
     According to some embodiments of the invention, it is further proposed that a wind power installation pylon is at least in part constructed from pylon segments according to embodiments of the invention. In that case, at least two pylon segments are assembled in plane-wise relationship to provide a pylon portion or pylon section, wherein the pylon segments are fitted together in joint-to-joint relationship and are connected together by way of the connecting bodies. Such pylon portions are then arranged in mutually superposed relationship, wherein higher pylon portions usually become increasingly smaller in diameter. The pylon portions in that case are so arranged in mutually superposed relationship that adjacent pylon portions have mutually displaced joints or mutually displaced gaps formed in the region of the joints. 
     Preferably, there is provided a wind power installation having a wind power installation pylon according to embodiments of the invention or a plurality of pylon segments according to embodiments of the invention. The operational life of the wind power installation can sometimes also be prolonged or maintenance intervals extended by the use of pylon segments according to embodiments of the invention or a pylon according to embodiments of the invention. 
     According to some embodiments of the invention there is also proposed a process for the production of a plurality of pylon segments for a wind power installation pylon. 
     In accordance therewith a plurality of pylon segments are simultaneously produced in a mould or shuttering. For that purpose a reinforcement and the connecting bodies including the anchoring thereof are prepared in the mould or shuttering in question for each respective one of the pylon segments to be produced at the same time. In that respect, anchorage can signify welding the connecting bodies to some reinforcing bars of the reinforcement. In that respect it is not an important consideration whether such welding is effected on site in the mould or is effected previously in a further preparatory step. 
     When the reinforcement and the connecting bodies are in their positions the mould can be filled up with concrete. The concrete must now initially set before it can be removed. Removal usually means that the concrete firstly remains in place and rather the mould or shuttering which here is generally of a multi-part configuration is removed. 
     The concrete mould or shuttering is provided for a complete pylon portion, that is to say a tubular casing portion which is completely closed in the peripheral direction. A corresponding concrete part and in particular a corresponding steel reinforced concrete body is thus produced when concrete setting occurs as described above. The connecting bodies provided are accordingly always arranged in pairs, more specifically there is always a respective connecting body for each two adjacent pylon segments. 
     For transport purposes the resulting pylon segments, such as, for example, two half-shells, are separated. At the location for erection of the wind power installation those segments are now assembled again in the way in which they were already arranged relative to each other in the described manufacturing process in the concrete mould. That makes it possible to achieve a high level of manufacturing accuracy and in particular very good adaptation of the pylon segments to be connected, to each other, as they were already necessarily adapted to each other in the mould. Separation of the pylon segments produced in that way in a concrete mould can be effected, for example, by the provision of separation layers at the joints, like a separation plate. 
     The use of closure means, such as, for example, a rubber sheathing, makes it possible to prevent the cavity or the recess of a connecting body becoming clogged when the concrete is introduced into the mould. 
     According to embodiments of the invention, there is also proposed a connecting body, in particular a steel recess, as has already been described hereinbefore in connection with a pylon segment. That connecting body includes: a connecting wall for attachment to a connecting wall of a second connecting body, a first side wall connected to the connecting wall, and two second side walls which are connected to the connecting wall and the first side wall so that the connecting wall, the first side wall and the two second side walls together form a recess. 
     A pylon segment can thus be furnished by the provision of such a connecting body and the construction of a wind power installation pylon from such pylon segments can be simplified. 
     Preferably two different connecting bodies which are respectively adapted to each other are provided as the connecting bodies. In the joint region in which they are fitted together, one has a depression and the other has a corresponding raised portion. Preferably therefore such connecting bodies are prepared in pairs and fitted in pylon segments in such a way that the corresponding connecting bodies, and in particular steel recesses, come to bear against each other and the corresponding regions engage into each other. Thus it is also proposed that there be provided a pylon segment which has two joint sides for attachment to one or two other joint sides of another pylon segment. At the one joint side a first connecting body having a depression is then next fitted and at the other joint side at least one second connecting body with a corresponding raised portion is fitted. In that way there can be provided a plurality of pylon segments which are then suitably assembled when erecting a wind power installation pylon. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       The invention is described by way of example hereinafter by means of embodiments with reference to the accompanying Figures. 
         FIG. 1  shows a perspective partly sectional view of a region of a wind power installation pylon according to the invention. 
         FIG. 2  shows a plan view of the non-sectioned region of a wind power installation pylon as shown in  FIG. 1 . 
         FIG. 3  shows a sectional side view along section line A-A in  FIG. 2 . 
         FIG. 4  shows a further view of a region of a wind power installation pylon as shown in  FIG. 1 . 
         FIG. 5  shows a perspective sectional view of a pylon portion assembled from two pylon segments according to one embodiment of the invention. 
         FIG. 6  shows a part from a joint region of two interconnected pylon segments according to one embodiment the invention. 
         FIG. 7  shows a portion of two pylon segments according to one embodiment of the invention in a joint region as a plan view and a partly sectional view. 
         FIG. 8  shows a perspective view of a connecting body according to one embodiment of the invention. 
         FIG. 9  shows a plan view of the connecting body of  FIG. 8 . 
         FIG. 10  shows a side view of the connecting body of  FIG. 8 . 
         FIG. 11  shows a front view of the connecting body of  FIG. 8 . 
         FIG. 12  shows a side view of a first and a second interconnected connecting body. 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter identical references can denote similar elements of different embodiments. 
       FIG. 1  shows a region  2  of a wind power installation pylon according to one embodiment of the invention as a perspective partly sectional view. The region  2  is composed of two pylon portions  4  or pylon sections  4  which are arranged one above the other on their end faces  5 . Each pylon portion  4  is respectively composed of two pylon segments  1 . Two respective pylon segments  1  are assembled at joints  6 . In the region of two joints  6  there is a respective gap or join  8  which however is comparatively thin and which can basically be disregarded. In actual fact, a gap is avoided by the abutting joint-to-joint arrangement. Arranged in the region of each joint  6  are six connecting bodies, of which the recess  10  that is accessible from the exterior can be seen here. Thus six pairs of connecting bodies and thus six pairs of recesses  10  are arranged at each gap  8 . In that case, the connecting bodies are connected together in pairs. Screws can be tightened in the recesses for making the connection. 
     The gaps  8  of the lower pylon portion  4  are arranged displaced relative to the gaps  8  of the upper pylon portion  4  of the wind power installation pylon region  2  shown in  FIG. 1 . Thus the gaps  8  of mutually superposed pylon portions  4  are not in alignment, whereby the overall stability of the wind power installation pylon can be improved. 
     The displacement of the connecting bodies  12  and therewith the recesses  10  can be particularly clearly seen from the plan view in  FIG. 2 .  FIG. 2  also clearly shows that each pylon portion  4  is composed of two pylon segments  1  in the shape of half-shells.  FIGS. 3 and 4  show further views of the region  2  of the wind power installation pylon. 
       FIG. 5  shows a further view in isolation of two pylon segments  1  which are fitted together and connected at their joints  6 . The cut-out portion shown in  FIG. 6  illustrates the arrangement of two pylon segments  1  in the region of their joints  6 . Each two connecting bodies, of which only some can be seen in  FIG. 5 , are arranged opposite each other in the region of the joints  6  and thus in the region of the gap  8  and are fixed to each other. For that purpose each connecting body  12  has a connecting wall  14 . 
     In that case, each connecting body  12  is let or concreted into the pylon segment  1  in such a way that the respective connecting wall  14  terminates with the respective joint  6 . Because a respective connecting body  12  of the one pylon segment  1  is arranged at the same height as the connecting body  12  of another pylon segment  1 , their connecting walls  14  are respectively in contact in the region of the adjoining joints  6  or the gap or join  8 . Due to the paired relationship of two connecting bodies  12  they can thus be directly connected together and fixedly screwed together in order thereby to provide a firm connection between the pylon segments  1 . 
     It will also be clear from  FIG. 6  that the two pylon segments  1  can be fitted flat against each other in the region of their joints  6 . The gap or join  8  is basically vanishingly small and basically only appears at the surface. 
     It can also be seen from  FIGS. 1 to 6  that the recesses  10  are accessible from outside the respective pylon segment  1  but in that case from the interior of the wind power installation pylon. In particular,  FIG. 1  also shows in the view at bottom right a gap or join  8  which faces towards the outside of the pylon. No recesses  10  can be seen there and they are therefore not accessible from the outside of the pylon from the exterior of the wind power installation. 
       FIG. 7  shows a plan view of a partly sectional cut-away portion of two pylon segments  1  which are fitted to each other. It is to be seen that any sectional surfaces are not provided with hatching, for the sake of improved clarity of the drawing. The two pylon segments  1  in  FIG. 7  are fitted together in the region of their joints  6 . In this case  FIG. 7  does not show any intermediate space between the joints  6 . 
     The sectional view on an enlarged scale makes the structure of the connecting bodies  12  clearer, which essentially each have respective connecting walls  14  which bear against each other in the region of the joints  6 . Each connecting body  12  has a first side wall which, however, cannot be seen in the  FIG. 7  view. In addition, a second side wall  18  of each connecting body  12  is shown. Each second side wall  18  is respectively connected to the connecting wall  14  in question. 
     First reinforcing bars  20  are fixed to the first side wall and second reinforcing bars  22  are fixed to each second side wall  18 . The first reinforcing bars  20  are slightly inclined relative to the second reinforcing bars  22 . For example, in the illustrated embodiment of  FIG. 9 , the inclination is about 4 degrees. Further angles of inclination can possibly be provided between the reinforcing bars. 
     Thus, the connecting bodies  12  are fixed together in the region of the connecting walls  14 . Any forces are transmitted by the respective connecting wall  14  to the first side wall and the second side wall  18  and from there further by way of the first reinforcing bars  20  and second reinforcing bars  22  to the respective pylon segment in which the reinforcing bars  20  and  22  and thus the connecting bodies  12  are anchored. 
     The perspective view in  FIG. 8  shows a connecting body  12  in the form of a connecting box or steel recess. It has a connecting wall  14  with a first side wall  16  connected thereto and two second side walls  18 . The connecting wall  14 , the first side wall  16  and the two second side walls  18  together form a recess. Two second reinforcing bars  22  are fixed to each second side wall  18  and four first reinforcing bars  20  are fixed to the respective first side wall  16 .  FIGS. 8 to 11  show the reinforcing bars  20 ,  22  of a terminated length. The reinforcing bars  20 ,  22  can, however, also be longer and in addition there can be a connection to further reinforcing elements, in a situation involving anchorage in the respective pylon segment  1 . 
       FIG. 8  also shows two connecting openings  24  in the connecting wall  14 . Those connecting openings  24  are basically in the form of bores and are suitable for passing a screw therethrough, in which case a screw head or a screw nut can bear against a surface of the connecting wall  14 , that is towards the recess  10 . 
     The plan view in  FIG. 9  of the connecting body  12  shows a second side wall  18  and a part of the connecting wall  14 .  FIG. 9  is identified as a plan view as the present view corresponds to a direction of view from above downwardly for the case involving an appropriate arrangement in an erected wind power installation pylon. The inclination between the first reinforcing bars  20  and the second reinforcing bars  20  is identified as the angle of inclination  26  in  FIG. 9 . 
       FIG. 10  shows a view of the recess  10  in the connecting body  12 . The recess  10  is provided between the first side wall  16 , the connecting wall  14  and the two second side walls  18 . It is also clear from  FIGS. 8 to 10  that the reinforcing bars  20 ,  22  are arranged set back somewhat behind the connecting wall  14 . 
     The front view in  FIG. 11  shows the arrangement of the connecting openings  24  in the connecting wall  14  and shows that the connecting wall  14  is basically bordered by three sides, namely the first side wall  16  and the two second side walls  18 . The connecting wall  14  and therewith the connecting openings  24  are also bordered on three sides by the first and second reinforcing bars  20 ,  22  in order thereby ultimately to provide for load transmission by way of the connecting wall  14  to the reinforcing bars  20 ,  22  and from there into the corresponding steel reinforced concrete body of a pylon segment. 
       FIG. 12  shows a first connecting body  30  which is fixedly connected and screwed to a second connecting body  32  by means of screws and nuts  40  and  42  respectively. The connecting bodies  30  and  32  in this case are fitted to each other in the region of their connecting walls  14 ′ and  14 ″. In the region of the connecting wall  14 ′ the first connecting body  30  has a depression  34 . That depression thus also involves a depression relative to a joint  6 ′ of the first connecting body  30 . For that purpose the second connecting body  32  as a counterpart has a raised region or an elevated portion or a raised portion  36  in the region of its connecting wall  14 ″. In this case the raised portion  36  also rises above a joint  6 ″ and is provided for being fitted into the inset region or the depression  34 , as shown in  FIG. 12 . That improves connecting properties, and it is possible at any event for the first connecting body and the pylon segment in which it is let to prevent the connecting body, namely the illustrated steel recess, from projecting, even when slight manufacturing tolerances are involved. 
     Moreover, the various embodiments described above can be combined to provide further embodiments. These and other changes can be made to the embodiments in light of the above-detailed description. In general, in the following claims, the terms used should not be construed to limit the claims to the specific embodiments disclosed in the specification and the claims, but should be construed to include all possible embodiments along with the full scope of equivalents to which such claims are entitled. Accordingly, the claims are not limited by the disclosure.