Expansion Joint For Road Works

Abstract

A concrete roadway having a joint between adjacent sections is provided with two plates, one secured upon each section, at the ends. The plates have interdigitating fingers to carry traffic over the joint. The plates are so tightly secured to the concrete by bolting that they remain in compression even when traffic is passing over the joint.

Description

FIELD OF THE INVENTION

The invention relates to an expansion joint for roadways such as bridge roadways, comprising sections of concrete laid end to end so as to have small gaps between ends of concrete sections at the joints.

SUMMARY OF THE INVENTION

One purpose of the invention is providing an expansion joint making it possible to assure the continuity of the road from one section of concrete to the next for the passage of vehicles. More particularly, the invention provides such an expansion joint that is inexpensive to make, easy to lay and small in size, while assuring excellent attachment of the joint to the sections of road so as to minimize the effect of repeated passage of vehicles over the joint.

The invention has for an object, an expansion joint for roads such as, but not limited to, bridge roadways, comprising two metal elements, each carried by one of the two adjacent sections of the road whose two ends face each other, each of the metal elements comprising a plurality of teeth arranged side by side, extending in cantilevered fashion, from said element, toward the other element and going into the spaces separating the corresponding teeth of said other element, a support for said teeth forming with said teeth a single metal piece, a lower support face that is fairly planar to rest on a part of said portion of the road supporting said element, and attachment means, comprising at least a rod that is fairly perpendicular to said support face and carries at one of its ends a means of attachment onto said element and on its other end a means of attachment on to said portion of the road supporting said element, at least one of said attachment means being movable along said rod and working with a member making it possible to pull it with a predetermined force in the direction of the other of said attachment means.

BRIEF DESCRIPTION OF THE DRAWING

The invention will now be explained more in detail with the aid of the accompanying drawing, in which:

FIG. 1 is a longitudinal sectional view of a joint according to the invention;

FIG. 2 is a top plan view of the joint of FIG. 1; and

FIG. 3 is a longitudinal sectional view, similar to FIG. 1, of a modification of the joint of the invention.

Referring first to FIGS. 1 and 2, the expansion joint represented comprises two metal parts 1 and 2 carried respectively by two sections 3 and 4 of the concrete roadway whose ends 5 and 6 face one another. (The concrete roadway is shown surfaced with a conventional road surfacing agent, e.g. macadam.) Each of the two metal elements comprises a support 7, or 8, from which there extend in the direction of the end of the corresponding portion of the work, parallel, elongated teeth 9 or 10. These teeth extend along a plane parallel to the upper face of portions 5 and 6 on which the road surface is placed. The teeth 9 and 10 interdigitate, as can be seen in the figure, teeth 9 going into the spaces separating teeth 10 from one another. These teeth form, with the support, which they extend across a single metal piece resembling a comb that can be made of steel, a weather-resisting light metal alloy or the like.

Each of the metal elements 1 and 2 rests on portion 5 or 6 by a fairly planar lower support face comprising, for element 1, the lower face 11 of support 7 and the lower face of a metal plate 12 which is located under the part of teeth 9 which is not overhanging in relation to end 5 or portion 3. Between portion 5, on the one hand, and support 7 and plate 12, on the other hand, is placed a mortar bed 13. Of course, element 2 is made in the same way and its lower face 14 and the lower face of a plate 15, rest on a mortar bed 16 laid on portion 4. As can be seen in FIG. 1, ends 17 and 18 of teeth 9 and 10 have their upper edge aligned with the upper edges of the bases of teeth 9 and 10, of supports 7 and 2 and the roadway. On the other hand, the vertical height of the ends of teeth 17 and 18 is small in comparison with the vertical height of said teeth at their base, so that at the time of bringing portions 3 and 4 together, end 17 of a tooth 9 can slide horizontally above plate 15, while end 18 of tooth 10 can move in an identical way above plate 12. Thus, a great support surface is obtained for elements 1 and 2, associated with a considerable path due to the length of teeth such as 9 and 10, without supports 1 or 2 of the teeth being large.

Attachment of element 1 on portion 3 is performed by means of rods 19 fairly perpendicular to support face 11 and going into said portion. These rods 19 can, for example, be inserted in orifices made by pipes 20 which assure the formation of the orifice at the time the concrete is cast. The lower end of rod 19 is screwed into a force distributing piece 21 including an annular flange 22, but which could also be in the shape of a truncated cone, the small base of the frustum of the cone being located on the side of support 7. This piece 21 makes it possible to secure the rod in portion 3. The other end of rod 19 can receive an element such as a nut 23 which can rest on support 7 by means of a washer 24 and which acts as an element for attachment on element 1. It can be seen that by tightening nut 23 or threaded rod 19, it is possible to lock the lower support face, made up of support 7 and plate 12, with such a force that the passage of the vehicle wheels over the overhanging ends 17 of teeth 9 creates in the rest of the parts making up the joint only a reduction of the compression forces exerted by the tension of rod 19. Thus is avoided the mechanical fatigue due to the alternating compression and traction forces which occur in the joints of the prior art. Moreover, the prestressing created in the concrete of portion 3 because of the tightening of nut 23 makes it possible to involve a greater mass of concrete in the attachment of element 1.

Of course, instead of being buried in portion 3, head 21 could rest on the lower face of the portion through which rod 19 would pass all the way through. In such case, head 21 could also be replaced by a nut working with a washer such as 24. Of course, elements other than nuts could be used to pull the support with predetermined force toward portion 3.

Referring now to FIG. 3, an embodiment is shown which is intended for joining two portions 3 and 4 that are relatively close together. Elements 1 and 2 include teeth 25 and 26 which are not so elongated as are the teeth in the preceding example. The shape of teeth 25 and 26, looked at from above, can be, for example, equilaterally triangular. Between the two elements 1 and 2 is placed a compressible fluid-tight fitting 27, preferably made of a shape of hollow extruded elastomer presenting at least a lengthwise interior cavity so as to permit, at the time of bringing elements 1 and 2 together, the horizontal edges of this fluid-tight fitting 27 to be deformed in the direction of said cavity. Thus, at the time of compression of the fitting, the size of the fitting need not increase in the direction perpendicular to that of the compression. Fitting 27 is preferably adhered to the elements 1 and 2, which may be roughened where the adhering is to take place. A suitable adhesive is used. Shorter teeth 28, 29, can be provided in elements 1 and 2, below teeth 25 and 26 to form with them a sort of cage in which fitting 27 is captive.

Between element 1 and portion 3, on the one hand, element 2 and portion 4, on the other hand, is inserted, before mounting of the expansion joint, a sheet 30 of flexible plastic material which includes a central free part 31 placed under teeth 25 and 26. This free part 31 forms a fold under the action of the weight. Sheet 30 thus makes it possible to prevent moisture from coming in between the ends of portions 3 and 4.

It should now be apparent that the expansion joint for road works as described hereinabove possesses each of the attributes set forth in the specification under the heading "Summary of the Invention" hereinbefore. Because the expansion joint for road works of the invention can be modified to some extent without departing from the principles of the invention as they have been outlined and explained in this specification, the present invention should be understood as encompassing all such modifications as are within the spirit and scope of the following claims.

Claims

What is claimed is:

1. For carrying traffic over the gap between ends of two adjacent concrete sections of a road, an expansion joint comprising:

two metal elements, each including a support for extension upon one end of one section and a plurality of teeth extending in one direction laterally from the support for traversing the gap, said teeth being spaced from one another along said support, the ends of said teeth having their upper edge substantially aligned with (1) the upper edge of the bases thereof, (2) said support and (3) the road; each support having means defining a generally planar lower support face for supporting the support on the respective section end; means defining at least one opening through the support and through the support face; and means for securing the two metal elements upon the ends of the respective adjacent sections, so that the teeth of the two metal elements are interdigitated; the securing means for each metal element comprising: at least one rod extending generally perpendicular to said support face, means engageable with the section for anchoring the lower portion of the rod against upward movement with respect to the section; said rod, above said anchoring means extending up through said opening means; and vertically adjustable securement means on said rod above said opening means tightenable, in combination with the anchoring means, to provide such compressive force on said supports that when vehicular traffic passes over the joint a reduction in compression, but not an alternation between compression and tension, is created in said supports.

2. The expansion joint of claim 1 wherein said teeth are elongated.

3. The expansion joint of claim 2 further including, for each metal element, a plate underlying the bases of the teeth thereof, said plate being secured to said teeth and said support face extending onto said plate.

4. The expansion joint of claim 2 wherein said teeth decrease in vertical height as said teeth extend from the respective supports.

5. The expansion joint of claim 1 wherein said supports are spaced from one another and engagingly receive between them, below said teeth a tubular extrusion of flexible material, said extrusion being compressed between said supports.

6. The expansion joint of claim 5 wherein said supports, where they engage said extrusion are roughened; and further including adhesive means securing the extrusion to the roughened portions of said supports.

7. The expansion joint of claim 1 wherein the upper ends of the rods are threaded and the adjustable securement means comprise nuts threadable on the threaded upper ends of the rods; and further including a washer interposed between each nut and each respective support.

8. The expansion joint of claim 7 further including a tubular pipe for each rod, each tubular pipe being arranged to be cast into the concrete, receive the respective rod and have the upper and lower ends of the rod protrude therefrom; the anchoring means comprising an annular flange on each rod exposed below the respective tubular pipe.

9. The expansion joint of claim 1 further comprising a sheet of flexible plastic material underlying the support faces of both metal elements and having sufficient slack to hang in a fold in the gap.