EP0163759B1 - Bridging device for expansion joints in bridges or the like - Google Patents

Abstract

The arrangement for covering over a gap in a roadway has bars running across the roadway. The bars are supported by transverse beams spanning the gap obliquely and which are supported at their ends in joint gap edge structures in such a way that the ends of the beams are able to slide and swivel in relation to the edge structures. The bars are carried on the beams by friction-reducing bearing parts so that sliding of the bars is possible. The bars have openings through the structure thereof (as for example holes in the bar itself or in a frame fixed thereto) to take up the beams and the bearing parts are adapted to allow sliding without swiveling between each bearing part and the associated beam and to allow swiveling between the bearing part and a bar joined thereto. The bearings are made of elastically yielding material and each have at least one bearing body. To ensure efficient transmission of horizontal forces by the bearing bodies to the transverse beams with only a small pre-loading effect (to stop the bearing bodies being lifted clear of the transverse beams by tilting moments) the bearing bodies are shaped generally as blocks and run in respective grooves of the transverse beams.

Description

The invention relates to a bridging device for expansion joints in bridges or the like. With slats extending transversely to the longitudinal axis of the traffic route; the cross beams, which are rotatably and displaceably supported on both sides in the joint edges and which bridge the joint diagonally to the longitudinal axis of the traffic path, are pivotably mounted via friction-reducing bearings, the cross beams being inserted through openings in or on the underside of the slats and the bearings being designed as sliding pivot bearings, each of which have at least one bearing body engaging on the upper side of the cross member and one bearing body engaging on the underside of the cross member, which are non-rotatably connected to the cross members and displaceable in their direction of extension and pivotably connected to the slats.

Such a bridging device is already known (DE-C-2 746 490). There, the bearing bodies are designed as cylindrical disks, each having a groove for slidably receiving the upper section or the lower section of the cross member of a rectangular profile. The bearing bodies are installed under considerable vertical preload.

Such a bridging device must absorb vertical forces (wheel loads) and horizontal forces (braking and acceleration forces) which act on the lamellae and transmit them to the joint edges. The horizontal forces act in the direction of the longitudinal axis of the traffic route or transversely to the direction of extension of the slats and at a longitudinal point of the slat, so that they are effective in a corresponding distribution on the two adjacent cross members. As a result of the inclination of the beams, the proportionate horizontal force acts obliquely to the likewise horizontal beam, it being possible to divide it into a longitudinal component and a transverse component, based on the cross member. The longitudinal component is introduced into the cross member to a certain extent in accordance with the vertical preload of the bearing body. In addition, there is a relative displacement between the crossbeam and the lamella, which thus avoids a higher load. In this respect, the power transmission works with a slip clutch effect. The transverse component, on the other hand, must be transferred fully from the bearing bodies to the cross member and must therefore be introduced into the joint edges.

The horizontal force at the point of intersection of the lamella and cross member also leads to a torque, since it acts on the cross member with a lever arm, the length of which corresponds approximately to the vertical distance between the top of the lamella and the cross member center. The moment exerted by the longitudinal component is unproblematic because, on the one hand, this force is limited in accordance with the “slipping clutch effect” due to the relative displaceability between the lamella and the cross member, and on the other hand, this tilting moment can be absorbed at the ends of the cross member with a correspondingly large lever arm. On the other hand, the absorption of the tilting moment caused by the transverse component around the longitudinal axis of the beam is more critical. In this respect, there are comparatively large loads on the bearing body, the upper bearing body being stressed on one side of the cross member and the lower bearing body being stressed on the other side of the cross member, while the opposite bearing body sides are pulled off the cross member. These conditions could lead to a harmful lifting of the bearing body from the cross member, which is associated with noise and rapid destruction of the bearing body. This is counteracted in the known design by increasing the pre-tension of the bearing body in the interest of the “slip clutch effect” to such an extent that the lifting of the bearing body under the loads that occur is prevented. In contrast, the tilting moment is not absorbed by the groove engagement between the bearing bodies and the cross member. The bearing body projections, which laterally delimit the groove, only act as a lateral guide and for the transfer of horizontal forces to the cross member. The bearing bodies are not able to absorb torque loads.

Thus, the vertical preload of the bearing body must be measured according to the maximum torque occurring about the longitudinal axis of the cross member. However, this affects the slipping clutch effect and makes it difficult to avoid the plates under high loads. It should be taken into account that the preload of the bearing body is reduced by relaxation over time, so that this also means that a particularly high initial preload must be used.

Accordingly, the invention has for its object to carry out the transmission of forces or moments from the slats to the cross member so that a high bias of the bearing body and the associated reduction in their useful life can be avoided, so that the adjustment of the bias of the bearing body only can be chosen from the viewpoint of expediency for the slip clutch effect.

This object is achieved in that the bearing body is substantially cuboid and are each guided through the side walls of a groove provided in the top and bottom of the cross member. It is known that in the case of a joint bridging device the bearing bodies are cuboid and arranged in groove-like depressions between projections on the top or on the bottom of cross members (DE-B-2 004 634). There, the depressions of the cross beams have a width which considerably exceeds the corresponding dimension of the bearing body, so that the two lateral beam projections do not normally interact with the bearing body in the sense of guidance. Rather, the projections merely form stops which permit transverse movements of the bearing bodies with respect to the cross member to a limited extent. With such a construction, a positive inclusion of a tilting moment is not possible. It is also not necessary in the known joint bridging device, because there the cross members run at right angles to the slats and thus in the direction of the longitudinal axis of the traffic route. The horizontal forces that occur thus act in the direction of the crossbeams, so that there are no force components which lead to a tilting moment about the longitudinal axis of the crossbeams.

In the embodiment according to the invention, there are comparatively large guide surfaces between the cuboid bearing bodies and the side walls of the cross member grooves. The transverse guidance of the bearing bodies achieved thereby secures them against tilting movements and harmful lifting off the cross member. The bearing body can be placed under a vertical preload, which is dimensioned so that the slats show the desired evasive behavior. At the same time, this vertical preload also means an additional measure of security against the harmful lifting of the bearing body from the cross member. This is a comparatively low vertical preload, which is associated with low friction between the bearing bodies and the cross member. The bearing bodies not only have a considerably longer service life, so that the repair and maintenance effort is reduced, the manufacture of the bearing bodies is also simplified due to their cuboid shape with smooth boundary surfaces.

The bearing bodies are expediently installed under vertical prestress. In this case, the vertical preload is preferably selected so that the plate can withdraw from the further load absorption by moving on the cross members against the frictional forces dependent on the vertical preload when a predetermined maximum braking force is exceeded. In addition, the vertical preload can exert a certain relief on the guide surfaces on the bearing bodies and the cross beams from occurring tilting moments about the longitudinal axis of the beam.

The bearing bodies advantageously consist of an elastomer and are provided on their sliding surface and on the opposite surface with a plate made of abrasion-resistant, low-friction material. This plate is expediently a steel plate which is provided with a sliding layer.

It is also advantageous if the plates each have a circular blind hole in the surface opposite the sliding surface, into which a circular disk-shaped guide pin engages, which protrudes from a plate welded to the lamella. In this way, despite the cuboid design of the bearing bodies, they can be pivoted relative to the slats.

In an expedient embodiment, the bearing bodies have a length such that a gap remains between the slats that are pushed together, while the end faces of the bearing bodies of each cross member are already in contact with one another. This ensures that no noise is generated by the slats touching each other when the slats are passed over. The minimum distance remaining between the slats is expediently about 5 mm.

In the interest of a high load capacity, all cross members are expediently connected to all the slats by means of a sliding pivot bearing.

The crossmembers are advantageously limited in their displacement by means of stops arranged in the joint edges. This measure means that the crossbeams cannot slide out of the joint edges. In this case, further sliding pivot bearings can be provided in the recesses of the joint edges to support the ends of the cross members.

In a preferred embodiment, at least three cross members are provided and run alternately in opposite directions at an angle to the slats. The opposite orientation of the oblique crossbeams leads to an overall good absorption and introduction of the various forces from the slats into the joint edges.

• Fig. 1 einen Vertikalschnitt durch die Überbrückungsvorrichtung in Richtung quer zur Fuge;
• Fig. 2 zwei Gleitschwenklager an der Unterseite einer Lamelle, die jeweils in die Nuten zweier Querträger eingreifen ;
• Fig. 3 eine vergrößerte Detaildarstellung in einem vertikalen Schnitt, wobei sich die Lamellen im zusammengeschobenen Zustand befinden ;
• Fig. 4 eine Draufsicht auf einen mittleren Teil der Überbrückungsvorrichtung bei der zusammengeschobenen Stellung gemäß Fig. 3.
• Figuren 5 bis 7 : jeweils schematisch die Draufsicht auf die Überbrückungsvorrichtung mit minimaler, mittlerer und maximaler Fugenöffnung.

An exemplary embodiment of the invention and the equally spaced setting of the slats within the respective joint width are explained in more detail below with the aid of a schematic drawing. Show:

• 1 shows a vertical section through the bridging device in the direction transverse to the joint.
• Figure 2 shows two sliding pivot bearings on the underside of a lamella, each of which engage in the grooves of two cross members.
• 3 shows an enlarged detail view in a vertical section, the slats being in the pushed-together state;
• 4 shows a plan view of a central part of the bridging device in the pushed-together position according to FIG. 3.
• Figures 5 to 7: each schematically the top view of the bridging device with minimum, middle and maximum joint opening.

FIG. 1 shows one of the cross members 1, which runs obliquely to the plane of the drawing, with two slats 2 and 3 supported thereon. An edge lamella 5 or 6 is connected to each joint edge body 4. The two ends of the cross member 1 each protrude into a cavity 7 of the associated joint edge body 4.

In the spaces between the slats are each sealing body 8 made of rubber-elastic profile pieces that do not hinder the pushing together of the slats. The slats 2 and 3 can have openings through which the cross members 1 are inserted or have a U-frame 18 on their underside, which circumscribes an opening 9. The slats 2 and 3 are supported on the cross beams 1 via sliding pivot bearings, each of which consists of an upper bearing body 10 and a lower bearing body 11. The bearing bodies 10 and 11 are essentially cuboid. At the ends of the cross member stops 11 a, which limit the displacement of the cross member in both directions, are provided.

FIGS. 2 and 3 show the precise design of the bearing bodies 10 and 11. 2 and 3 is accommodated in the U frame 18 arranged on the underside of a lamella 17. Its legs are attached to the underside of the lamella 17 by welding. A plate 16 with a guide pin 19 is welded to the underside of the lamella 17. The guide pin 19 engages in a circular blind hole 20 of a steel plate 21, with which the bearing body 10 is provided on the surface 23 opposite the sliding surface 22.

The lower bearing body 11 is fastened in a corresponding manner to the U-frame 18, a plate 16 provided with a guide pin 19 being welded to the U-frame. The guide pin 19 in turn engages in the circular blind hole 20 of the steel plate 21.

The bearing bodies 10 and 11 are arranged in a groove 24, which is formed in the top and bottom of the cross member 1, in which the bearing bodies are guided by the side walls 25. The side walls 25 also serve to transmit horizontal forces from the lamella 17 to the cross member 1.

Figures 3 and 4 show the bridging device with minimal joint opening. In this state, the bearing bodies 10 and 11 of the respective cross members 1 abut one another with their end faces 26. A minimal gap 27 remains between the lamellae, which has a size of approximately 5 mm. This design reliably prevents the slats from touching one another under the action of horizontal forces and thereby generating undesirable noises.

FIGS. 5 to 7 each show the top view of a bridging device, only cross members and slats being shown schematically. The total of four slats 1 are supported on a total of four cross members Q and q. The cross beams are mutually aligned and slanted to the slats, i. that is, two cross members Q are to the right and two cross members q are inclined to the left. Each cross member is connected to each lamella by means of a slide bearing G according to FIGS. 1 to 3. Since the pivot points of the slide bearings are fixed with respect to the lamellae, a change in the joint width inevitably results in a pivoting and displacement of the crossbeams Q with respect to the lamellae 1, which are always parallel to one another. In FIG Cross beams shown. FIG. 7, on the other hand, shows the maximum open joint, which has a width of approximately 80 mm, the distances between the lamellas increasing and the angle formed between two adjacent cross members decreasing at the same time.

FIG. 5 shows the smallest possible joint, the bearing bodies abutting one another. The angle enclosed between adjacent cross members Q and q increases compared to the central position shown in FIG. 6. As a result of the sliding swivel bearing connection, the slats must be uniformly adjusted to one another regardless of the respective joint width. The gap between the slats and the gap between the Randia slats and the joint edges are the same size for each joint width according to the play of each slat control.

Claims (11)

1. Bridging device for expansion joints in bridges or the like, comprising bars (2, 3 ; 17) running athward the longitudinal axis of the roadway, which are pivotally arranged by means of friction-reducing bearings on transverse beams (1), each of which is swivelingly and slidingly supported at its two ends in the joint edges (on 4) so as to bridge over the joint at an angle to the longitudinal axis of the roadway, the transverse beams (1) being placed through openings (9) in the bars (2, 3 ; 17) or on the lower sides thereof, and the bearings being designed as slide and swivel bearings each having at least one bearing body (10) acting on the upper side of the transverse beam (1) and one bearing body (11) acting on the lower side of the transverse beam (1), which are connected non-rotatingly with respect to the transverse beams (1), slidingly in the direction of extension thereof and pivotally with respect to the bars (2, 3 ; 17), characterised in that the bearing bodies (10, 11) generally have the form of a block and are guided by the side walls (25) of a groove (24) provided in the both upper and lower sides of the transverse beam (1).

2. Device according to claim 1, characterised in that the bearing bodies (10, 11) are mounted in a way that they are vertically biased.

3. Device according to claim 1 or 2, characterised in that the bearing bodies (10, 11) are made of an elastomer and that their sliding faces (22) as well as the opposite surfaces (23) are provided with a plate (21) of abrasion-proof and low-friction material.

4. Device according to claim 3, characterised in that the plates (21) are steel plates surfaced with a slide covering.

5. Device according to claim 3 or 4, characterised in that the surface (23) opposing the slide face (22) of the plates (21) has a circular blind hole (20) with a circular diskshaped guide pin (19) fitting into said hole and projecting from a plate (16) welded on the bar (2, 3 ; 17).

6. Device according to any of the claims 1 to 5, characterised in that the length of each bearing body (10, 11) is such that gaps (27) remain between the bars (2, 3 ; 17) pushed together, while the end faces (26) of the bearing bodies (10, 11) of each transverse beam (1) already abut each other.

7. Device according to claim 6, characterised in that each gap (27) is 5 mm in width.

8. Device according to any of the claims 1 to 7, characterised in that all transverse beams (1) are connected to all bars (2, 3 ; 17) by means of slide and swivel bearings.

9. Device according to any of the claims 1 to 8, characterised in that the shifting motion of the transverse beams (1) is limited by stops (11a) disposed in the joint edges.

10. Device according to any of the claims 1 to 9, characterised in that further slide and swivel bearings are provided in recesses of the joint edge structures for supporting the ends of the transverse beams (1).

11. Device according to any of the claims 1 to 10, characterised in that at least three transverse beams (1) are provided, which extend obliquely in opposite direction to the bars (2, 3 ; 17) in alternating succession.

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