a) Field of the Invention
The invention relates to a formwork element of a round formwork comprising a form skin, on whose backside vertically extending profile rails are disposed, with which horizontal curved shaping bars are detachably connected.
b) Description of Related Prior Art
Formwork elements of this type are known. In order to implement one side of the round formwork (e.g. the outer formwork) from such formwork elements, several formwork elements of this type, to be arranged next to and/or above one another, are connected with one another. The outer and inner formwork can herein be developed analogously. In the region between the vertically extending profile sections, the concrete pressure is borne by the form skin. The shaping bars, also referred to as anchor rails, determine the curved shape of the formwork element. Further, these shaping bars conventionally form the bearing surface and abutment for the anchors of formwork anchored through.
Such formwork elements are reusable. If herein the radius of curvature of the round formwork is to be for example smaller than in the preceding application, the roundness of the dismounted shaping bars is contoured to the required greater curvature by plastic deformation with an appropriate rounding device. Since the shaping bars are disposed radially further inwardly than the form skin, the shaping bars would, after the contouring, project laterally beyond the form skin. The shaping bars are therefore cut correspondingly in order to terminate laterally flush with the form skin. If the formwork element is to be applied in a subsequent use for the production of a round formwork with greater radius of curvature (=smaller curvature), the shaping bars must be replaced since the previous shaping bars are now too short.
Apart from round formworks, in which the shaping bars are deformed by plastic deformation to the desired curvature by means of an appropriate rounding device, mechanical systems are also known, in which the shaping bars comprise articulations, which can be adjusted according to the desired curvature of the formwork element. Of disadvantage herein is the complicated structuring and the elaborate adjustment work of the articulations.
One important object of the invention is providing a formwork element of the above described type, which, at simple structuring can be employed for different radii of curvature of the round formwork without cutting the ends of the shaping bars or a replacement of these shaping bars being required.
Consequently, according to the invention one length-adjustable shaping bar is provided. In the case of an inner formwork the shaping bar can thereby be shortened for a greater curvature and, in the case of a lesser curvature, it can be lengthened or, in the case of an outer formwork, it can be lengthened with a greater curvature and shortened with a lesser curvature, such that in each instance it terminates at the edge of the form skin. As a function of the curvature, the cast elements are therein offset relative to one another at variable width. In the case of an inner formwork, the smallest radius curvature for which the formwork element can be employed, is that [radius] at which the cast elements terminate without offset against one another at the side edges of the form skin. In the case of an outer formwork, this is the case at the greatest radius of curvature for which the formwork element can be employed.
The connection of the shaping bars with the vertically extending profile rails preferably takes place via the shoes. For this purpose, these [shoes] can comprise a first clamping part in contact on the profile rail as well as a second clamping part gripping the cast elements on their sides facing away from the form skin, the clamping parts being braced by means of a tightening bolt penetrating bores in the clamping parts and in a web, parallel to the form skin, of a particular profile rail.
In a preferred embodiment of the invention above and beneath a longitudinal opening of the shaping bar at least two cast elements, in contact with one another, are available, of which in each instance at least one extends toward the particular front-side end of the shaping bar. Through the longitudinal openings can penetrate anchor rods for the anchoring through of the formwork.
The cast elements are preferably implemented in the form of plates, thus have the form of a flat rectangle in cross section. Such flat elements can most readily be contoured with the least deformation by means of rollers.
Further advantages and details of the invention will be explained in the following in conjunction with the embodiment example depicted in the drawing. Further objects of the invention are evident therefrom.
In the drawing depict:
In
On the backside of the form skin 1, facing away from the form surface 2, several vertically extending profile rails 3, 4 are disposed, e.g. bolted on. Herein two boundary-side profile rails 3 are available, which preferably have a U-form cross section. Each of the open sides of the U-form cross sections of the two boundary-side profile rails 3 faces away from the edge of the formwork elements. The profile rails 3 comprise webs 9, in contact on the backside of the form skin 1 and fastened with the form skin 1, webs 5 extending from webs 9 at the edge and perpendicularly to the form skin 1, and webs 6, extending at the ends of webs 5 remote from the form skin 1 extending from these webs 5 parallel to the form skin 1. The webs 5 perpendicular to the form skin 1 are preferably flush with the front-side ends 7, 8 of the form skin 1.
Between the boundary-side profile rails 3 are disposed at a spacing from one another several vertically extending profile rails 4 on the backside of form skin 1. These profile rails 4 are preferably implemented such that they have a Z-form cross section. They are fastened on form skin 1 with the webs 10 in contact on the backside of form skin 1. From the edge of web 10 projects a web 11 vertically with respect to the form skin, and on the end of web 11, remote from the form skin 1, extends a web 12 extending parallel to the form skin 1. The distances between adjacent profile rails 3, 4 are determined by [the mechanical laws of] statics and can be, for example, in the range between 50 cm and 1.5 m.
With the vertically extending profile rails 3, 4 are detachably connected horizontally extending shaping bars 13. The shaping bars 13 are curved in the horizontal direction, whereby the curvature of the formwork element is determined in the horizontal direction. By varying the curvature of the shaping bars 13 the curvature of the formwork element can be varied.
The more precise implementation of the shaping bars 13 will be explained in the following in conjunction with FIGS. 2 to 9. In the depicted preferred embodiment example, each of the shaping bars 13 comprises four cast elements 14 held together by means of shoes 15. The cast elements 14 are preferably implemented in the form of plates, thus, viewed in cross section, have the form of a flat rectangle. Each of these cast elements 14 extends over a large portion of the longitudinal extent of the shaping bars, but are at least for all curvatures of the shaping bars 13, except for the greatest (in the case of an inner formwork) or the least (in the case of an outer formwork) for the curvature, designated for this formwork element, shorter than the total length of the shaping bar 13. The cast elements 14 are offset relative to one another in the longitudinal direction of the shaping bar 13, and specifically in the depicted arrangement of the two inner cast elements 14 extend up to the front-side end 16, shown in
If all cast elements 14 extend without mutual offset v at both front-side ends of the shaping bars 13, the greatest (in the case of an inner formwork) or the least (in the case of an outer formwork) curvature is designated for this formwork element.
All of the cast elements 14 have preferably the same length, but they can also be of different lengths.
As stated, the shoes 15 serve for holding together the cast elements 14 and furthermore for preventing them from buckling or being twisted about a horizontal (curved) axis extending in the longitudinal direction of the shaping bar 13. The connection of the shaping bar 13 with the vertically extending profile rails 3, 4, furthermore, preferably takes place via the shoes 15.
In the embodiment example according to FIGS. 2 to 7 each particular shoe 15 is formed by two U-shaped clamping parts 18, 19, which are braced with one another by means of a tightening bolt 20. Each clamping part 18, 19 has a base shank 21 and two side shanks 22. In the side shanks 22 two slots 24 are recessed starting from their free longitudinal edge 23. The slots 24 in the two side shanks 22, viewed in side view (
One of the two clamping parts 18, 19 is in contact on web 6 of the profile rail 3 or on web 12 of profile rail 4. In web 6 or 12 a bore is disposed congruent with bore 25. Into the slot 24 of this clamping part 18 are introduced the one side edges of the cast elements 14. Onto the opposite side edges of cast elements 14 is slipped on the second clamping part 19. In the depicted embodiment example the second clamping part 19 is implemented identically to the clamping part 18, but placed in position rotated by 180 degrees about a horizontal axis and by 180 degrees about a vertical axis relative to the clamping part 18. By means of the tightening bolt 20 penetrating web 6 or 12 and the clamping parts 18, 19, the clamping parts 18, 19 are braced against one another and fastened on the profile rail 3 or 4, respectively. The tightening bolts 20 in the depicted embodiment example are formed by bolts in connection with nuts.
At each point of intersection of the shaping bar 13 and the profile rails 3, 4 is preferably provided a shoe 15 for holding together and aligning the cast elements 14 and for fastening the shaping bar 13 on the profile rails 3, 4. Into the two boundary-side shoes 15 the cast elements 14, spaced apart from the particular front-side end 16, 17, project at a greater or lesser distance and (with smaller curvatures of the formwork element in the case of an inner formwork, or at greater curvatures in the case of an outer formwork) can also terminate before the boundary-side shoe 15. It is in principle also conceivable and possible to provide for this situation a boundary-side shoe with slots 24 implemented in one or both side shanks of the clamping parts 18, 19, the width of which slots corresponds only to the thickness of a single cast element 14.
Between the upper cast elements 14 in contact on one another and the lower cast elements 14 in contact on one another is located a longitudinal opening 26 of the shaping bar 13. Through it can extend an anchor rod 27 of an anchor, such as is shown in
The connection of several formwork elements disposed one above the other can take place in conventional manner, for example by means of tubular pieces 30 disposed at the lower edge of the formwork element, which [tubular pieces 30] are placed onto tubular pieces disposed on the upper end of the lower formwork element and are screwed together with them by means of threaded bolts. For centering the tubular pieces 30 conical recesses 31 and corresponding truncated cone-form extensions (not shown in the Figures) to engage into the conical recesses 31 can be provided.
Formwork elements to be disposed one next to the other can be bolted together via their boundary-side profile rails 3, whose webs 5 are in contact on one another. In the webs 5 bore holes 32 can be disposed for the passage of threaded bolts.
To achieve continuous rigidity of the shaping bars 13 between formwork elements laterally adjoining one another, the shaping bars 13 of the adjacent formwork elements can also be connected with one another via connection units. One possible implementation of such a connection unit is shown schematically in
To achieve continuous rigidity between laterally adjoining formwork elements, it would also be conceivable and possible to dispose at levels between the shaping bars 13 preferably horizontally extending connection rails, which extend over both adjoining formwork elements and which are connected with at least one of the profile rails 3, 4 of a particular formwork element. They are here preferably in any case connected with the two boundary-side profile rails 3, adjacent to one another, of the two formwork elements. The connection rails could herein be implemented analogously to the shaping bars 13 and their connections with the profile rails 3 and/or 4 could also analogously take place by means of shoes 15.
If the curvature of the formwork element is to be changed, the tightening bolts 20 are loosened, whereupon the cast elements 14 can be dismantled. The cast elements 14 are plastically deformed to the desired curvature with a contouring device (by means of appropriate rollers). The shaping bars 13 are subsequently reassembled, the cast elements 14 being correspondingly offset, and the tightening bolts 20 tightened. In the proximity of the two front-side ends 16, 17 of the shaping bars 13 at least the particular cast elements 14, extending up to these front-side ends 16, 17, should extend through the boundary-side shoes 15. The shaping bars 13 can thereby be connected with the boundary-side profile rails 3.
A further modified embodiment example of a clamping part 18 of a shoe is depicted in
At the front-side ends 7, 8 the form skin is preferably provided with an edging protection 42. (
Various modifications of the depicted embodiment example of the invention are conceivable and possible without going beyond the scope of the invention. For example, more or fewer cast elements 14 can be provided. It would also be conceivable and possible, for example, that the shaping bar 13 is formed by two cast elements 14 implemented such that they are U-shaped in cross section, which are correspondingly offset in the longitudinal direction of the shaping bar 13. In order to make possible an interspace for the passage of anchor rods 27, it could also be provided here to place the two U-shaped cast elements with the free ends of their side shanks in contact with one another, the free ends of the side shanks being locally provided with indentations for the formation of the longitudinal opening.
It would also be conceivable and possible to implement the boundary-side profile rails 3, instead of in the depicted U-shaped implementation, in the same manner as the profile rails 4, thus as Z-profiles. The web extending spaced apart from the form skin 1 and parallel to the form skin 1 could in this case be disposed for example pointing away in each instance from the side edge of the formwork element. The web vertical with respect to the form skin 1, would, in case of the Z-form implementation of the profile rails 4, be spaced apart from the front-side end 7, 8 of the formwork element. The shaping bars 13 can extend beyond this web to the particular front-side end 16, 17 and preferably, again, terminate flush with it. To connect two laterally adjoining formwork elements, again, connection rails could be provided disposed at levels between the shaping bars 13 and connected with the profile rails 3 and/or 4. In addition, at levels between the shaping bars 13 or the connection rails, respectively, plate-form elements could be bolted onto the webs, spaced apart from the form skin 1 and extending parallel to it, of the adjacent profile rails 4 in order to be able to absorb shearing forces acting in the vertical direction.
U-form or Z-form implementations, other than those depicted and described, of the profile rails 3, 4 would also be conceivable and possible, for example such having the form of an H.
As is evident based on the above description, the scope of the invention is not limited to the depicted embodiment examples, but rather should be determined with reference to the attached claims together with their full range of possible equivalents.
While the above description and the drawing represent the invention, it is obvious to a person skilled in the art that various changes can therein be carried out without leaving the true spirit and scope of the invention.
Number | Date | Country | Kind |
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A 2020/2003 | Dec 2003 | AT | national |