US3822428A

US3822428A - Joint inserts for bridging expansion joints

Info

Publication number: US3822428A
Application number: US00334297A
Authority: US
Inventors: W Stog; R Springer
Original assignee: Stog KG Ind & Rohrleitung
Current assignee: Stog KG Ind & Rohrleitung; STOG W KG IND und ROHRLEITUNGSBAU DT
Priority date: 1972-07-19
Filing date: 1973-02-21
Publication date: 1974-07-09
Anticipated expiration: 1991-07-09
Also published as: NL7211329A; CA977199A; DK144303C; DE2235413B2; DD98130A6; NL171917C; NL171917B; DE2235413A1; DK144303B

Abstract

A joint or gap insert for bridging expansion gaps in structures, especially bridges, which includes strip means of elastic material having recess means with an arcuate cross section arranged within that region of the strip means which in installed position of said insert will be located within the region of the expansion gap to be bridged while reinforcing means extend into the strip means and are adapted to be firmly connected to the structure, the expansion gap of which is to be bridged.

Description

nited States Patent [19] Sing et al..

[ JOINT INSERTS FOR BRIDGING EXPANSION JOINTS [75] Inventors: Wilhelm Stog; Reinhard Springer,

both of Waltrop, Germany [73] Assignee: W. Stog KG, Industrieund Rohrleitungsbau, Waltrop, Germany 22 Filed: Feb. 21, 1973 21 Appl. No.: 334,297

[30] Foreign Application Priority pata July 19, 1972 Germany... 22 35413 52 us. (:1 14/16,'5 2/573, 404/65 [51] 1111.0. Elc 1.1/ [58] Field 61 Search 14/16; 404/64, 65, 68; 52/573, 396, 471

[56] 3 References Cited UNITED STATES PATENTS 3,375,763 4/1968 Welch 14/16 3,720,474v 3/1973 FOREIGN PATENTS OR APPLICATIONS 1,051,881 12/19 Great Piritain 404/65 H Ill 6 M Jam-w Stog 14/16 [11] 3,822,428 1 July 9,1974

3/1967 Germany 404/ 1/1970 France 14/16 Primary Examiner-John E. Murtagh Attorney, Agent, or FirmWalter Becker 1 1 ABSTRACT A joint or gap insert for bridging expansion gaps in structures, especially bridges, which includes strip means of elastic material having recess means with an arcuate cross section arranged within that region of the strip means which'in installed position of said insert will be locatedwithin the region of the expansion gap to be bridged while reinforcing means extend into the strip means and are adapted to be firmly connected to the structure, the expansion gap of which is to be bridged.

4 l2 Clain 1 s, 3 Drawing Figures PATENTEDJUL 9 m4 SHEET 3 BF 3 Fig. 3

2s 63 e1 23 21. 2a

1 JOINT INSERTS FOR BRIDGING EXPANSION JOINTS This invention relates to inserts for bridging expansion gaps in structures, in particular bridges, which inserts comprise a strip of elastic material held on either side of the expansion gap in grooves provided in the roadway, while in that zone of the strip which points in the direction of the expansion gap there is provided at least one recess extending parallel to the expansion gap.

With a gap strip of this type there is provided at least one-recess so that when the strip is compressed it will not buckle too much and will not be lifted out of the supporttherefor. It has been found, however, that these recesses which usually have a rectangular shape, are subjected to heavy wear in thevicinity of their corners. Moreover in the case of relatively long gap strips, the zones lying between? the recesses are lifted off locally from the roadway grooves supporting thev strip. In this way, dirt and moisture enters between the underside of the strip and the roadway groove and are able to reach the lateral strip fastening members. Furthermore, in the case of considerabledeformation of the strip, there exists the danger that its free side faces will be lifted off from the adjoining seal compounds or the like. This, too, permits moisture to enter.

It is, therefore, an object of this invention to obviate the drawbacks in the gap insert described above, and in particular to provide a gap strip which will be able to compensate for a relatively strong compression of the strip without undergoing any substantial deformation.

These and other objects and advantages of the invention will appear more clearly from the following specification, in connection withthe accompanying drawings, in which: 1

FIG. I is a cross section through a gap insert according to the invention which is relatively narrow, but can expand to a relatively considerable extent.

FIGS. 2 and 3 illustrate gap inserts for a relatively great expansion.

According to the present invention there is provided a gap or joint insert for bridging expansion gaps in structures such as bridges, which includes a strip of elastic material such as rubber material or other suitable elastic material such as synthetic elastomers. The strip of elastic material is held on either side of the expansion gap in grooves in a roadway, while in the zone of the strip directed towards the expansion gap there are provided recess means extending parallel to the expansion gap, said recess means being arcuately curved in cross-section with the cross-sectional are extending in a direction transverse to the longitudinal direction of said expansion gap, thereby exerting a stabilizing effect on said strip. 1

In this way the advantage is obtained that when the strip is subjected to compression or expansion, the tensions occurring inside the strip are diverted uniformly to the fastening members provided in the edge zones. The additionally provided stabilizing means aid in ensuring that the deforming forces within the strip are diverted and any occurringdisplacements of the materials will not lift the strip off from the bottom of the grooves or from the laterally adjoining roadways or intermediate inserts.

Advantageously, each recess is very shallow.

Each recess may have an eccentric convex shape. In this connection it is advantageous if in the longitudinal direction of the strip the recess has numerous consecutively arranged eccentric convexities of relatively short linear extension, which are alternately orientated towards one or the other one of the mountings.

According to another embodiment of the invention, ribs are provided inside the arcuately curved recess, in spaced relationship to each other, said ribs extending transverse the expansion joint. Advantageously, the ribs form a single piece with the strip.

In gap inserts where relatively high expansion may be expected, there may be provided two parallel recesses, each being parallel to the expansion gap. Both recesses may be eccentn'e'ally curved, while domes or arches thus formed are orientated toward the mountings.

Referring now to the drawings in detail, an expansion gap is provided between the two

parts

11 and 12 of a structure, such as abridge, road or the like. The substructure consists of concrete and has -a surfacing 13 with an asphalt layer 14 which forms the roadway surface. The surfacing 13 generally consists of bitumen and rests on the substructure with an insulating water repellent synthetic material layer 15 interposed therebetween, More specifically, such layer may consist e.g.,

' of an aluminum foil cemented by a bitumen or other known water repellent layer as commonly used in road building. The layers l3, l4, 15 do not extend to the expansion gap 10, whereby roadway grooves are formed for accommodating a gap strip. In the illustrated embodiment'of the invention, each

structural part

11 and 12 has an angle iron 16 which is parallel to the expansion gap and which has a horizontal flange l7 and a vertical web 18. The flange 17 is fastened to the bottom 19 of the roadway recesses by welding it to a reinforcement 20 which is provided in the substructure. A T- piece 22 is, by means of threaded bolt 25, connected to the free upper surface 21 of the flange 17, said T- piece 22 having a flange 23 and a-web 24. The web 24 is made inthe. form of a rib which extends upwards into the marginal area of a strip 26 of elastic material. Advantageously, the strip 26 is joined to the rib 24 by vulcanization. r

In addition thereto, a resilient angle plate 27 is secured to the upper surface of the horizontal flange 23 of the T-piece 22 by means of the bolt 25. The vertical arm of plate 27 bears against the free side face 28 of the strip 26 under preload, which latter is generated by tightening the nut of the bolt.

In the embodiment shown in FIG. 1, the angle iron 16 has essentially the basic'shape of an inverted T so that the horizontal flange 17 extends into the flange portion 35. The insulating synthetic material layer 15 extends to the horizontal flange portion 35 and may also extend upwardlyparallel to the web 18. The space between the resilient angle plate 27 and the vertical web 18 or the adjoining asphalt layer 14 and thesurfacing or cover 13, is, after the bolts havebeen fixed in position, sealed by sealing compound 29, inserted elastic strips or the 7 side faces 28 of the strip 26. Its cross section may be trapezoidal or rectangular or, as shown in FIG. 3, substantially triangular in shape, the surfacing 13 and the asphalt layer 14 being continued up to the inclined side face 72 and if necessary into the recesses 71. In the roadway zone only a narrow band of the section element 70 is exposed, which is provided with a tip or nose 73 which prevents the adjacent roadway surfacing from being pushed up on the face 72. The angle iron 16 may be omitted when section element 70 is used, and may be replaced by a plate 76-which is welded to the reinforcing member 20. Within the region of the expansion gap 10, the plate 76 has a bent-over edge 75 which serves as a reference edge during shuttering for setting the reinforcing member 20 in concrete and may be reinforced by a rib. Below the plate 76 there may be applied a layer 77 of viscous-elastic synthetic material, e.g. a two-component resin, especially eposy resin, which after concreting, is injected through the opening for the bolts 25 between the plate 76 and the upper surface of the structure 12 and when hardened has approximately the same hardness as concrete. Any cavities are thus sealed and the formation of damp chambers is prevented.

As will be evident from the drawings, the vertical web 24 of the T-piece 22 may in certain circumstances be deflected; this is illustrated by the inclined web 24'. In this way, the fixing in position of the strip 26 on the ribs or

webs

24, 24 is improved.

A recess 30 is formed on the underside of the gap strip, and extends in the direction of the expansion gap 10. This recess has the shape of a shallow curve which in the embodiment shown in FIG. 1 is eccentric. Moreover, with the embodiment of FIG. 1, the recess has in the longitudinal direction of the strip 26 numerous seriesly arranged eccentrically arched portions which have a relatively short linear extension. According to FIG. 1, the arched portion 30 is located in the sectional plane, and the arched portion 30' therebehind. The arched portion 30 is offset relative to the eccentrically arched portion 30 so that its dome 61' is adjacent the right-hand mounting, while the dome 61 of the arched portion 30 is adjacent the left-hand mounting. Viewed from below, the sloping

edges

62, 62 of the

arched portions

30 and 30 form ribs which engagewith one another like fingers. Therefore, in the event of the strip 26 being compressed, the material is not only deformed in the direction of the compression movement, but also transversely thereto. Inside the strip, an- S-shaped main stress line occurs. The same applies to expansion of the strip.

It is also possible merely to provide ribs inside the curved recesses. These ribsextend transverse the expansion gap and are arranged at a given distance apart from one another, which, according to the size of the strip may amount to between and 40 cm.

In the embodiment according to FIG. 2, two arcuately curved recesses 30 are provided which extend longitudinally with the same cross section over the entire length of the strip and parallel to the expansion gap 10, i.e., transverse the roadway. The recesses 30 are eccentric, their domes 61 being orientated toward the lateral mountings. Inside the recesses 30, ribs 63 are arranged so as to taper trapezoidally towards the bottom 19 of the roadway grooves. The ribs terminate somewhat above the bottom of the roadway grooves.

The ribs 63 of adjacent recesses 30 need not be in alignment with one another. Advantageously they are offset relative to each other so that when the strip 26 is compressed, a deformation takes place, such as has been described in connection with FIG. 1.

The ribs 63 may be provided with rigid inserts, as indicated at 64. These rigid inserts 64 assist in ensuring that when a compression of the strip occurs, the latter is deformed in an even more pronounced S-shape, if the ribs 63 do not align with one another, or if the ribs 63 are in alignment with one another, the gap strip 26 is pressed in the central zone between the recesses 30 onto the bottom 19 of the groove.

It is, of course, to be understood that the present invention is, by no means, limited to the specific showing in the drawings, but also comprises any modifications within the scope of the appended claims.

What we claim is:

1. An insert for bridging a gap of an expansion joint in structures including fastening elements having sides fixed in location and free of movement, especially bridges, which comprises preloaded strip means of elastic material secured to stationary sides of the fastening elements of structures independently of temperature and having recess means arranged within that region of said strip means which in installed support position of said insert will be located within the region facing the gap to be bridged, said recess means having an unsymmetrically arched arcuate cross section with the crosssectional are extending in a direction transverse to the longitudinal direction of said gap and thereby having a middle range of movement with a stabilizing effect upon said strip means to hinder lifting thereof in installed support position.

2. An insert according to claim 1, in which said recess means have an eccentrically arched contour.

3. An insert according to claim 2, in which said recess means comprise a plurality of recesses of an eccentrically arched shape transverse to expansion joint, and in which said recesses are arranged one behind the other when viewing them in the longitudinal direction of said strip means, the arched portion of said recesses alternately being located on different sides of the longitudinal plane of symmetry of the expansion gap to be bridged.

4. An insert according to claim 3, in which said recess means are provided with ribs extending transverse to the gap to be bridged.

5. An insert according to claim 4, in which said ribs form one integral single piece with said insert.

6. An insert according to claim 4, in which said recess means include two parallel recesses extending over the width of said insert strip.

7. An insert according to claim 6, in which each of said two parallel recesses has a dome-shaped portion and a substantially straight portion, said straight portions being adjacent to each other.

8. An insert according to claim 4, in which the ribs ofhadjacent recesses are offset with regard to each ot er.

9. An insert according to claim 4, which includes rigid reinforcing inserts arranged in said ribs. I

10. An insert according to claim 1, which includes rigid section elements engaging the prelateral surfaces of said strip, and bolt means extending through said rigid section elements for bolting down the latter.

11. An insert according to claim 10, in which said rigid section elements are under a slight preload for slightly preloading said strip.

12. An insert according to claim 1, in which the width of the arcuate portion of said recess means at a maximum equals half of the length thereof.

Claims

1. An insert for bridging a gap of an expansion joint in structures including fastening elements having sides fixed in location and free of movement, especially bridges, which comprises preloaded strip means of elastic material secured to stationary sides of the fastening elements of structures independently of temperature and having recess means arranged within that region of said strip means which in installed support position of said insert will be located within the region facing the gap to be bridged, said recess means having an unsymmetrically arched arcuate cross section with the crosssectional arc extending in a direction transverse to the longitudinal direction of said gap and thereby having a middle range of movement with a stabilizing effect upon said strip means to hinder lifting thereof in installed support position.

8. An insert according to claim 4, in which the ribs of adjacent recesses are offset with regard to each other.

9. An insert according to claim 4, which includes rigid reinforcing inserts arranged in said ribs.