Bridging Device

[0001] This is a continuation of PCT/EP2005/007280 filed Jul. 6, 2005, which is incorporated herein by reference in its entirety.

[0002] The invention relates to a bridging device for an expansion joint arranged between an abutment and an overhang in a structure used by motor traffic, in which the abutment and the overhang have recesses adjacent to the expansion joint, which are filled with polymer concrete, and in which a flat, rod-shaped retaining section of a metal edge profile is embedded in each recess and an elastic sealing profile extends between the two edge profiles, the elastic profile being sealingly connected to the two edge profiles.

[0003] Various versions of such bridging devices are known and used, particularly in viaducts, in order to compensate for changes in the length of the overhang caused by elongation due to heat. A distinction is made particularly between bridging devices with plates that are arranged inside the joint gap, between and parallel to the edges of the joint, and which are braced, on the one hand, against the cross-beams bridging the expansion joint and on the other, against the plate-free bridging devices. Bridging devices with plates are particularly suited for bridging expansion gaps with a relatively large working area (difference between maximum and minimum joint width). However, they are relatively expensive to produce and require a large installation space, and the installation is also complex and time-consuming. For these reasons, there is a tendency to use bridging devices without plates, whose fabrication and installation are both less complex. Especially attractive in view of both cost and the installation space required are bridging devices of the type cited above, which are described, among other places, in the commercial publication “Single-cell joint type RE with Robo®Flex” from Mageba SA, CH-Bülach, which was published after the date of priority of this application. These bridging devices can be installed in a very short time, because the edge profiles are not mechanically fixed by means of corresponding anchors directly to the load-carrying system of the overhang, or as the case may be, the abutment (i.e. in the case of a version involving an abutment and an overhang with a substructure and a roadbed placed on top of the substructure), but rather anchored by means of their flat, rod-shaped retaining sections in the recesses of the abutment or the overhang, which are filled with polymer concrete. “Embedding” of the retaining sections of the edge profiles in the polymer concrete, generally arranged on an essentially horizontal level, should be understood as indicating that the retaining sections are largely immersed in the polymer concrete, the polymer concrete being placed at least above and below the retaining sections. However, this anchoring of the edge profiles by embedding their retaining sections in concrete does not eliminate the additional possibility of the edge profiles, in some cases, being braced directly and mechanically on the respective load-carrying system, in which case the fitting position of the edge profiles is determined by means of the corresponding assembly-bracing, whereupon the installation position of the edge profiles is determined by means of the corresponding mounting supports, which do not however represent anchoring that carries any of the forces acting on the structure. However, one disadvantage of known bridging devices of the prior art is their use being limited to applications with a maximum operating range of approximately 80 mm (3.1496 inches), as there would otherwise be unacceptably high strain.

[0004] The objective of the present invention is to produce a bridging device characterized by particularly low fabrication and assembly costs, by means of which larger expansion joints can be bridged than is possible using conventional bridging devices of the prior art.

[0005] This objective is accomplished in terms of the present invention by having a toothed profile attached to the upper side of each edge profile, whose upper surface is essentially flush with the upper surface of the polymer concrete and the upper surface of the assigned abutment, or as the case may be, overhang, and whose teeth mesh respectively with the teeth of the other toothed profile. The present invention makes use of the insight that through utilization of the two toothed profiles that mesh with each other, the dynamic strain that acts on the edge profiles when motor vehicles pass over the bridging device can be substantially reduced compared to conventional bridging devices of the known art that do not have toothed profiles of this type. This makes it possible to use bridging devices of the type described at the beginning, which have particularly low fabrication and assembly costs and require only minimal installation space, without exceeding the admissible strain on the edge profiles due to dynamic shocks, even for applications where more complicated constructions have had to be employed due to the required size of the operating range. For example, bridging devices of the kind associated with this invention can also be used for structures in which the operating range of the expansion gap amounts to as much as 100 mm (3.937 inches) or even more. This obviously opens up completely new possibilities for application of the bridging device of the type described above, which is therefore extremely attractive in several respects.

[0006] The present invention is also particularly interesting with respect to the refitting of existing structures by replacing conventional bridging devices of any type with the device according to the present invention. It is significant in this context that the bridging device according to the present invention requires minimum height for its installation space, so that typically, in the case of a version of abutment and overhang with a substructure (particularly one made of structural concrete) and a roadway applied on top of that (especially one made of asphalt), the thickness of the roadbed is sufficient to accommodate the bridging device. This means that when there is a construction method of that type, a type to which the present invention is by no means limited, the recesses that are to be filled with polymer concrete do not generally have to extend into the substructure, but can be limited to the height of the roadbed. Another interesting aspect, particularly in relation to the refitting of existing structures, is the extremely short time required for the installation of the bridging device according to the invention, a significant contributing factor here being the circumstance that no direct mechanical anchoring of the edge profiles in the respective load-carrying system of the abutment and the overhang is required. The correspondingly short installation time for the bridging device according to the invention results in only a minimal closure period for the structure during its refitting.

[0007] With respect to the configurations presented here, it is particularly advantageous that the edge profiles of the bridging device are not anchored in a direct, mechanical, load-bearing manner in the load-carrying system of the abutment and the overhang, their (load-bearing) position in installation state being secured by the anchorage of the flat rod-shaped retaining sections in the polymer concrete, which fills the recesses in areas of the abutment and overhang that are adjacent to the expansion joint. In this context, it should be pointed out that a sheet-metal plate extending between the underside of the edge profile and the abutment, or as the case may be, from the overhang under the recess, which is affixed particularly to the edge profile and which defines the recess to be filled with polymer concrete on the side facing the joint, should not be seen as an anchoring of the corresponding edge profile on the load-carrying system any more than an additional bracing of the edge profile at certain points on the load-carrying system involved, which serves to keep the edge profile in its fitting position (see above) during mounting of the bridging device. Incidentally, in order to serve their purpose, these types of assembly supports are flexible, in order to exclude appreciable load transfer during operation; the cited assembly supports can, for example, incorporate spring elements.

[0008] With respect to a particularly advantageous removal of horizontal, vertical, and transverse forces, which are conducted through the toothed profiles into the edge profiles through the passage of motor vehicles over the bridging device, it is advantageous when the width of the recesses in the roadbed amount to between 2.4 and 4.0 times the value of the working range of the expansion joint, and it is particularly preferable that they be between 2.8 and the 3.3 times the value of the operating range of the expansion joint.

[0009] In accordance with another preferred further development of the invention, it is provided that the retaining sections of the edge profiles have apertures that are filled with polymer concrete. In this case, the area of each aperture amounts to at least 120 cm² (18.6 in²), and particularly advantageously, at least 180 cm² (27.9 in²). Through such apertures, the polymer concrete can be simply and efficiently poured into the recess area lying below the respective retaining section during the fitting of the bridging device in terms of the invention. This makes it possible for the retaining sections of the edge profiles to extend across virtually the entire width of the recess without this having disadvantageous effects on their embedding in the polymer concrete, which in turn has an advantageous effect on the elimination of the forces conducted via the toothed profiles into the edge profiles. In this sense, a preferred further development of the invention is distinguished by the width of the edge profiles, along with their retaining sections, amounting to more than 0.8 times the value of the width of the recesses, and especially advantageously, more than 0.85 times the value of the width of the recesses.

[0010] The total area of the aperture of each retaining section will preferably amount to 0.8 times and 2.0 times the value of the area (length×width) of the expansion joint at its mean width. A corresponding dimensioning of the apertures produces particularly advantageous conditions with regard to both the embedding of the retaining sections in the polymer concrete and load transfer. In this context, it is also significant that permeating the retaining sections with polymer concrete in the area of the apertures is also advantageous with reference to good anchoring of the edge profiles in the polymer concrete.

[0011] Even though there is no strict prescription for the shape of the apertures, it is nevertheless advantageous if the apertures are essentially rectangular and that their extent, in the longitudinal direction of the joint, is 1.4 to 3.0 times the value of the breadth of the strip remaining between neighboring apertures. This also contributes toward particularly favorable conditions for installation of the bridging device according to the invention, as well as its use. This kind of rectangular form for the apertures is not mandatory. They can also be constructed circular, oval, or elliptical, or have any other shape.

[0012] It particularly preferable to have the toothed profiles screwed to the edge profiles. This is seen as particularly advantageous with respect to rapid assembly of the bridging device, because the threaded holes in the edge profiles, into which the screws used for affixing the teethed profile will later be screwed, can initially be used for screwing in positioning traverses, which are placed on the roadbed of the overhang and the abutment, outside the recesses, in order to hold the edge profiles in their installation position, and for leveling. After the polymer concrete has set, the screws are unscrewed, the positioning traverses are removed, and the toothed profiles are screwed onto the edge profiles.

[0013] As far as the shaping of the toothed profile is concerned, the present invention allows for considerably leeway. In particular, tooth profiles that have a sinusoidal shape or zigzag toothed profiles with more or less rounded tips are potential options. The respective tips of the teeth can be slightly conical. Tooth height is adjusted to the operating range of the expansion joints.

[0014] The edge profiles used for the present invention can consist of a single piece. However, the versions that are especially preferable are those that are assembled from several parts, particularly when each of the edge profiles includes a fastening bar that is welded to a foundation bar which comprises the retaining sections, onto which the assigned toothed profile is affixed. This further development is especially advantageous in view of the production costs of the edge profiles.

[0015] According to another preferred further development of the invention, the sealing profile is configured as a humped hollow profile, the humped section extending into the space defined at the sides by the two fastening bars and from above by the two toothed profiles. This type of sealing profile (see DE 29907832 U1) in particular takes into account the potentially large operating range of the bridging device that this invention makes possible. It also prevents the accumulation of much too large amounts of dirt in the area above the seal. A corresponding configuration of the sealing profile for single-piece edge profiles is advantageous in the same way.

[0016] Finally, there is another preferred development of the invention that provides for hot application of joint sealant in the road surface area in the transition area from the abutment, or as the case may be, overhang, to the polymer concrete. In the event that the abutment and the overhang are executed with a substructure (in particular, one made of structural concrete) and a roadbed placed on top of that (in particular, one made of asphalt), this hot-application joint seals the transition between roadbed and polymer concrete.

[0017] The present invention is explained in more detail below on the basis of drawings depicting a preferred embodiment wherein:

[0018] FIG. 1 represents a vertical cross-section of a bridging device realized according to the terms of the present invention, which is installed in a structure, and

[0019] FIG. 2 represents a top view of the bridging device according to FIG. 1 (not mounted).

[0020] The bridging device 1 shown in the drawing serves to bridge an expansion joint 2 between an abutment 3 and an overhang 4, as provided in particular for a structure that can be driven on, such as a bridge. The abutment 3 comprises a substructure 5 consisting of structural concrete and a roadway 6, approximately 100 mm (3.937 inches) thick, consisting of asphalt, in which there is waterproof insulation 7 between the substructure 5 and the roadway 6. The overhang is also executed in the same way.

[0021] Adjacent to the expansion joint 2, the roadway 6 is recessed at both the abutment 3 and the overhang 4, to a respective width of approximately 300 mm (11.811 inches). The insulation 7 is also largely removed in the area of the recesses 8, however a narrow edge area 9 of the insulation 7 is retained in the area of the recess 8, in order to provide a connection between the insulation 7 and the polymer concrete 10 with which the recesses 8 are filled, its upper surface 11 being flush with the upper surface 12 of the adjacent roadbed 6. For the purpose of achieving a good bond between the polymer concrete 10 and the structural concrete of the substructure 5, the exposed surface of the structural concrete must be dry and sandblasted. The areas that are to be filled with polymer concrete (for example, “Robo®Flex” from the firm of Mageba SA, CH-Bülach), are each defined on the side facing the expansion joint by a stop-end sheet-metal plate 13, that is attached to the corresponding edge profile 14.

[0022] A flat rod-shaped retaining section 16 of a metal edge profile 14 is embedded in the polymer concrete 10, the edge profile being comprised of two flat rods that are welded to each other, i.e. a foundation bar 17 comprising the retaining section 16, and a fastening bar 18 that is welded to it. The fastening bars have threaded holes 19, into which the fastening screws are screwed, which respectively serve to fix one toothed profile 21 to the assigned edge profile 14. The surfaces 22 of the toothed profiles 21 are flush with the surfaces 11, or as the case may be 12, of the polymer concrete 10 and the assigned roadbed 6. The tooth height comes to approximately 100 mm (3.937 inches), which produces an operating range of the bridging device 1 of about 100 mm (3.937 inches).

[0023] Except for a narrow gap 23, the retaining sections 16 of the edge profile 14 extend to the edges 24 of the recesses 8, and have apertures 25 that are filled with polymer concrete 10. These apertures are essentially rectangular and about 170 mm (6.693 inches) long (in the longitudinal direction of the expansion gap) and approximately 140 mm (5.512 inches) wide (across the longitudinal direction of the expansion gap). The width of the strip 26 remaining between two adjacent apertures 25 amounts to approximately 80 mm (3.1496 inches). There is no direct anchoring of the edge profiles 14 in the substructure 3.

[0024] An elastic sealing profile 27 extends between the two edge profiles 14. This is sealingly connected to the two edge profiles 14 by means of each of the two edges 28 of the sealing profile 27 being fastened in a groove 29 of the corresponding edge profile. The sealing profile 27 is configured as a humped hollow profile, the humped section 30 extending through the space defined on the side by the two fastening bars 18 and from above by the two toothed profiles 21.

[0025] In the event of an assembly of abutment and overhang that deviates from the embodiment described above, in particular if it consists entirely of concrete that also forms the roadbed, the explanations given above apply in modified form. It is also obvious that the present invention could be modified in various ways by a person skilled in the art without departing from the principle expressed in the claims, for example by slanting or milling the edges defining the recesses in the abutment and overhang, in order to form undercuts that are filled with polymer concrete.