Abstract:
A driving pipe and method for the construction of an essentially horizontal pipeline, whose wall is made at least primarily of concrete polymer. At least sections of the wall of the concrete polymer pipe are made of a liquid-permeable filter material consisting of polymer-bound, gravel-like particles.

Description:
BACKGROUND OF THE INVENTION 
     The invention relates to a driving pipe for the construction of an essentially horizontal pipeline, whose wall consists at least primarily of concrete polymer. Driving pipes of this kind are used, for example, in the construction of sewers, where a major advantage is that the lines can be laid without having to dig a trench. 
     The horizontal drilling method for the installation of horizontal supply and disposal lines and filtering wells without trenches is known. However, this method is relatively complex, since an additional drilling machine must be used and thus the driving and the installation of the line coordinated in terms of the technical and work-related conditions. 
     In contrast, the driving method uses the pipeline as a means of transmitting the forces required for driving. This enables substantially less expensive construction of the line, although the design of the driving pipes must cater to the driving forces to be transmitted. As a result of the use of concrete polymer pipes, the finished line meets all practical operating requirements, including those relating to resistance to aggressive liquids and thus to service life. 
     Up to now, only concrete polymer driving pipes with a closed wall have been used to construct supply and disposal lines, where the seepage of liquid from the surrounding soil, or other materials surrounding the pipeline, through the pipe wall is neither possible nor intended. 
     BRIEF SUMMARY OF THE INVENTION 
     Consequently, the object of the invention is to design a driving pipe of the type described in the opening paragraph, which can also be used as a filter pipe or drainage pipe, e.g. to collect seepage water. 
     The object is solved in that at least sections of the wall of the concrete polymer driving pipe are made of a liquid-permeable filter material consisting of gravel-like particles being bound by a binder-material, especially by a polymer. 
     It has been found that, despite the weakening caused by the perforations, it is possible to dimension the wall of the pipes in such a way that they are capable of absorbing and transmitting the respective maximum driving force that occurs. 
     Specifically, the wall of the concrete polymer pipe can be provided with several perforations, each of which is filled with the liquid-permeable filter material. These perforations can be holes, although they can also be strip-shaped perforations running in the longitudinal direction of the pipe, for example, each of which is filled with correspondingly strip-shaped filter material. The pipe may consist partially, sub-stantially or completely of a concrete polymer material. 
     Further details of the invention are disclosed in the sub-claims. 
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
     The foregoing summary, as well as the following detailed description of preferred embodiments of the invention, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there is shown in the drawings embodiments which are presently preferred. It should be understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown. 
     Several practical examples of the invention are illustrated in the drawings. The drawings show the following: 
     FIG. 1 A perspective view of a driving pipe designed as a filter or seepage pipe, 
     FIG. 2 A section along Line II—II in FIG. 1, 
     FIG. 3 A view of a second configuration corresponding to FIG. 1, 
     FIG. 4 A view of a third configuration corresponding to FIG. 1 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Driving pipe  10  shown in FIGS. 1 and 2 is provided with round holes  12 , each of which is sealed by a plug  14  made of filter gravel. This plug  14  can be designed as a bonded gravel filter and consists of filter gravel and, for example, polyester or vinyl ester resin. These resins can also be used as the binders for the concrete polymer. This also applies to the following practical examples. 
     Filter plugs  14  have a void volume which allows the desired permeability for the liquid to be accommodated by pipe  10 . The compressive strength of plugs  14  is much lower than that of the concrete polymer of the surrounding wall. This, however, is not a disadvantage, since wall  16  as a whole is dimensioned such that it is capable of absorbing the load acting at maximum driving force. For example, a driving pipe according to FIGS. 1 and 2 with an inside diameter of 400 mm and an outside diameter of 550 mm, i.e. a wall thickness of 75 mm, can be provided with holes whose maximum diameter is 2.54 cm. These holes are arranged in the longitudinal direction of the pipe at intervals of 10.0 cm, for example, where the individual rows are also spaced 10.0 cm apart in the circumferential direction. In this context, the arrangement is such that the holes of two adjacent rows are offset relative to one another, as shown in FIG.  1 . 
     Face ends  18  of driving pipe  16  are designed in the usual manner of driving pipes. This also applies to the connecting elements for connecting two adjacent pipes and to any seals, etc. located between the two pipes. In this context, the generally standard and known designs and elements used to connect driving pipes for the construction of a pipeline can be provided and used. This also applies to the remaining practical examples described below. 
     The practical example according to FIG. 3 essentially corresponds to that illustrated in FIGS. 1 and 2, so that identical or corresponding parts are also labelled with the same reference numbers, each of these being increased by  100  in FIG.  3 . 
     Perforations  112  in pipe  110  in FIG. 3 are designed as strips running in the longitudinal direction of pipe  110 , these being sealed by correspondingly strip-shaped elements  114  made of filter material. The drawing shows that perforations  112  taper from the outside surface towards the inside, so that filter element  114  is roughly in the form of a truncated wedge. The filter elements sealing the perforations in the pipe wall can be prefabricated and, for example, fixed to the pipe wall using an adhesive. 
     In the configuration according to FIG. 4, parts that match or correspond to those in the configuration according to FIG. 1 are labeled with the same reference numbers, increased by  200 . In FIG. 4, the arrangement is such that recess  212  takes up a continuous, relatively large area extending, for example, over two-thirds of the length of pipe  210  and roughly 180° around pipe  210 . Consequently, the filter material that fills recess  212  also forms a continuous element  214 , which makes up a major part of the shell  219  of pipe  210 . One advantage of this design can be that, when installing pipe  210  in the manner illustrated in FIG. 4, the lower region of the inside pipe cross-section forms a channel for liquid drainage that is not interrupted by filter areas, through which liquid could also escape from pipe  210  under certain circumstances. The respective conditions will determine which of the respective configurations should be considered. 
     The teaching according to the invention can be applied in many respects, as it has been found that perforated pipes with holes filled by plugs made of filter material, and/or pipes that are provided with differently shaped, possibly also large-area, perforations filled with filter material, can also be used as driving pipes, at least if the dimensions of the pipes and/or the arrangement of the perforations take the necessity of transmitting the driving forces into consideration. The driving pipes according to the invention are suitable, for example, for constructing seepage lines in landfills, but also for the construction of essentially horizontal filtering wells. 
     It will be appreciated by those skilled in the art that changes could be made to the embodiments described above without departing from the broad inventive concept thereof. It is understood, therefore, that this invention is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the present invention as defined by the appended claims.