U.S. patent number 3,887,292 [Application Number 05/501,951] was granted by the patent office on 1975-06-03 for spanning joints.
This patent grant is currently assigned to Firma Korber-AG. Invention is credited to Waldemar Koster.
United States Patent |
3,887,292 |
Koster |
June 3, 1975 |
Spanning joints
Abstract
The invention relates to apparatus for spanning expansion joints
in public roads, consisting of marginal bodies, which are anchored
in the joint margins in an opposed arrangement, are disposed
adjoining the upper surface of the road and the joint and are made
of metal and rubber sections connected together by vulcanisation,
also comprising a lateral groove in each case, which is open in the
direction of the joint, for the sealing accommodation of the
fixture members of an elastic expansion body covering the
joint.
Inventors: |
Koster; Waldemar (Forsbach,
DT) |
Assignee: |
Firma Korber-AG (Glarus,
CH)
|
Family
ID: |
5898223 |
Appl.
No.: |
05/501,951 |
Filed: |
September 3, 1974 |
Foreign Application Priority Data
|
|
|
|
|
Nov 15, 1973 [DT] |
|
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2357108 |
|
Current U.S.
Class: |
404/69; 14/73.1;
52/396.05 |
Current CPC
Class: |
E01D
19/06 (20130101); E01C 11/126 (20130101) |
Current International
Class: |
E01C
11/02 (20060101); E01D 19/06 (20060101); E01C
11/12 (20060101); E01D 19/00 (20060101); E01c
011/02 () |
Field of
Search: |
;404/69,47,68,64,65,66
;14/16 ;52/396 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Byers, Jr.; Nile C.
Attorney, Agent or Firm: Drucker; William Anthony
Claims
What is claimed is:
1. In a device for spanning expansion joints in roads, comprising:
marginal bodies of metal and elastomeric material anchored in the
joint margins in an opposed arrangement and disposed adjoining the
road surface and the joint, said bodies having a lateral groove
with an aperture which is open in the direction of the joint for
the sealing accomadation of members of an elastic expansion body
covering the joint, the improvement in which each marginal body
comprises an intermediate layer of rubber, on the underside of
which is a metal mounting anchored in the joint margin; and on the
upper surface of the intermediate layer there is a metal plate, the
groove being defined at least in part by the intermediate layer,
the metal mounting and the metal plate.
2. In a device as claimed in claim 1, the improvement in which the
groove is formed with undercuts adjacent its aperture and which
extend transversely thereto, the outer areas of the undercuts being
disposed adjacent the metal plate on one side and the metal
mounting on the other.
3. In a device as claimed in claim 1, the improvement in which a
layer of wear resistant, elastomeric material is applied to the
metal plate.
4. In a device as claimed in claim 3, the improvement in which the
thickness of the layer is reduced from the edge of the roadway
covering adjacent the marginal body, in the direction of the joint,
and the metal plate extends in a correspondingly inclined
position.
5. In a device as claimed in claim 1, the improvement in which the
metal mounting and the metal plate are connected together at their
edges adjacent the roadway covering.
6. In a device as claimed in claim 1, the improvement in which the
metal plate is completely embedded in the intermediate layer.
7. In a device as claimed in claim 1, the improvement in which the
metal plate and/or the metal mounting have interuptions or
perforations formed therein.
8. In a device as claimed in claim 1 the improvement in which the
metal mounting is formed as a hollow bar which is downwardly open
and encloses a longitudinally displacable anchor bar extending
parallel to the joint.
Description
In a known device of this type (W. Koster,
Fahrbahnubergange-Roadway crossings, Developments 1965 to 1968,
Bauverlag G.m.S.H., Wiesbaden-Berlin, Page 14, Diag. 300) the
marginal bodies consist of steel profiles of C-shaped cross-section
and are provided with an anchoring rib, in the grooves of which an
expansion body is inserted at top and bottom along its opposed
lateral margins. This construction is particularly advantageous for
heavy traffic loads. Owing to the considerable height of the
structure and its robust construction, it is only of restricted
suitability for small construction joints, subject to slight
stress, for example, in the interior of buildings or pavements.
The need for elastic joint transitions for damping the impact of
wheels, was taken into account (cf. ibid. Page 20, Diag. 305), in
that joint transitions were provided comprising compound
constructions made of metal plates and neoprene expansion elements.
In these composite constructions there are difficulties in
attaining the necessary flexibility for adaptation to different
joint positions without reduction in stability. Mounting of these
composite constructions is also difficult, since, for their
fixture, they must be held in the joint margins with stress
deformation of the neoprene material. If the construction is
damaged it must be replaced on both joint margins.
A further known construction (French Patent No. 2128107) consists
of separate marginal bodies which are each connected to the
marginal edges, a plate spanning the joint being connected to one
marginal body and disposed so as to be capable of sliding movement
on the opposed marginal body, in the manner of a cover-plate. This
known construction is subject to abrasion and does not provide a
water-tight covering for the joint interstice.
A further known construction (Civil Engineering-ASCE, January,
1972, Page 36) utilises marginal bodies, substantially consisting
of rubber blocks, which are connected to each other by means of an
elastic expansion body covering the joint, the fixture members for
the expansion body thereby being secured in grooves in the marginal
bodies, which are open in the direction of the joint. There is a
risk of loosening of the connection if heavy vehicles travel over
the construction. This type of connection is always at risk, owing
to deformation of the rubber parts under stress.
The invention is based on the aim of providing a spanning device,
which damps the impact of traffic, is of durable construction and
is also adapted to withstand great stress, trouble-free anchorage
being attained simultaneously with small constructional height.
This aim is attained, according to the invention, in that the
marginal bodies each comprise an elastomeric intermediate layer on
the under-surface of which then is provided a metal mounting, said
mounting being anchored in the joint margin, and on the upper
surface of the intermediate layer there is provided a metal plate,
the groove being at least in part defined by the intermediate
layer, metal mounting and metal plate.
In a preferred embodiment of the invention the groove is
constructed in a known manner with undercuts extending adjacent its
aperture and transversally thereto, the outer areas of the
undercuts being directly or indirectly adjacent the metal plate on
one side and the metal mounting on the other.
According to the invention, a very firm seal for the fixture
members of the expansion body in the insertion groove is attained.
Arching of the regions of the marginal bodies adjacent the
insertion groove is eliminated by the groove being defined by the
metal plate and metal mounting on both sides, so that the expansion
body is effectively prevented from being torn out. The metal plate
and metal mounting simultaneously provide reinforcement of the
marginal bodies, and the elastic properties of the marginal bodies,
which damp the impact of wheels, are not impaired.
It is advantageous, for reasons of wear and tear, to dispose the
metal plate in such a manner that it adjoins the upper surface of
the roadway. In many cases of application, particularly for low
traffic loads, it is advantageous to apply a further covering layer
of wear-resistant elastomeric material on the metal plate. In order
to attain the most continuous and therefore smoothest possible
transition to the road surface, on travelling over the covering
layer, it is advantageous if the thickness of the covering layer
increases from the edge of the roadway covering, adjoining the
marginal body in question, as far as the joint interstice. This can
advantageously be effected if the metal plate is disposed or
constructed so as to extend downwards at an inclined angle from the
roadway covering in the direction of the joint interstice.
If desired the metal mounting and metal plate may be connected to
each other at their edges adjacent the roadway covering. Such a
connection should have a resistance to bending corresponding to the
elasticity of the elastomeric intermediate layer.
The metal plate can be fully embedded in the intermediate layer. By
this construction, a standard marginal body is obtained, which is
defined in the downward sense by the metal mounting and its
intermediate layer is connected to the covering layer in one
piece.
Specific embodiments of the invention will now be described by way
of example with reference to the accompanying drawings in
which:
FIG. 1 is a partial plan view of a covered joint;
FIG. 2 is a section taken along the line II--II of FIG. 1, on an
enlarged scale;
FIG. 3 shows a further embodiment, in section, cut transversally
relative to the lingitudinal sense of the joint;
FIG. 4 shows part of the embodiment according to
FIG. 3 in plan view, and
FIG. 5 shows part of the metal insert according to FIG. 3 on an
enlarged scale.
FIG. 1 shows, in plan view, part of the upper surface of a public
road for example the roadway of a bridge. The joint covered by the
spanning device extends vertically relative to the margin 1 of the
roadway. The plan view shows the left-hand marginal body 2 of the
joint, the right-hand marginal body 3 and the elastic expansion
body 4, which covers the joint and is secured laterally in the two
marginal bodies. The roadway coverings 5, 5a, made for example of a
surfacing, are attached to the marginal bodies 2, 3 in the
direction of the exterior.
The cross-section of the left-hand marginal body 2, shown in FIG.
2, illustrates the structure of a metal-rubber-composite
construction, for which natural or synthetic rubber can be
utilised. The marginal body 2 which is substantially of the same
width as the roadway covering rests on a concrete foundation 6 of
the joint margin. The concrete foundation is disposed adjoining the
joint on its right-hand margin 7. The joint interstice is covered
by the elastic expansion body 4, of which only the right-hand half
is shown by chain dotted lines. The structure of the right-hand
joint margin, not shown, complementarily reflects the illustration
according to FIG. 2.
The marginal body 2 consists of a metal plate, advantageously made
of an aluminium alloy, adjoining the roadway surface. The metal
plate is slightly profiled on its upper surface, in order to reduce
the danger of slipping, particularly when the roadway is wet.
Between the metal plate 8 and the metal mounting 9, constructed as
a hollow bar and made of steel or an aluminium alloy, an
intermediate layer 10 of elastomeric material is provided. The
intermediate layer 10 is permanently connected to the metal plate 8
and a metal mounting 9, for example by vulcanisation or adhesive. A
suitable rubber material for the layer 10 is a wear-resistant
elastomer of constant temperature, such as styrenebutadiene rubber,
butyl rubber or even natural rubber. The metal mounting 9 encloses
an anchor bar 11, which is made of steel and is anchored at
intervals in the concrete foundation 6 by means of bolts 12. The
steel bolts 12 can be welded to the anchor bar 11, as shown in FIG.
2; they can, however, also be connected thereto by screws. To
improve their fixture in the concrete foundation, pegs can be
inserted therein; in the event of the concrete foundation 6 being
formed by a concrete plate which is accessible from below, the
bolts 12 can pass completely through this concrete plate and can be
secured on the under surface of the concrete plate by a nut, not
shown. It is advantageous for the bolts 12 to be secured
eccentrically on the anchor bar 11, as shown in FIG. 2, so that
this rail is spaced as far as possible from the margin 7 of the
concrete foundation.
Owing to the structure of the marginal body, its mounting is, in
particular, also simplified. Pre-determined anchorage points no
longer need be provided, since the marginal body is capable of
displacement relative to the anchor bar. The anchor bar is
preferably constructed as a through bar. Shorter members can also
be provided in spaced arrangement, each such member being firmly
connected to the concrete sub-structure by one or more bolts
12.
The metal mounting 9 comprises an interstice, which is open in the
downward sense, for the passage of the securing bolts 12. The
interstice is formed by bending round the wall parts which form the
metal mounting. The wall parts adjoining the interstice, which are
curved back, rest on the upper surface 14 of the concrete
foundation 6. The ends 15, 16 of the curved members advantageously
extend laterally beyond the metal mounting 9 and thus form a broad
support surface on the concrete foundation 6. The end 15 of the
curved member disposed on the interior of the joint extends under
insulation 17 for the roadway covering 5.
The groove 13 for accommodation of the expansion body 4 is so
constructed in the intermediate layer 10, that its upper part is
defined by the metal plate 8 and its lower part by the metal
mounting 9.
In the embodiment according to FIG. 3, the metal mounting 9 is
constructed as an extruded or curved profile, integral with the
metal plate 8. The metal mounting 9 and metal plate 8 are connected
to each other by the curved piece 18. The intermediate layer 10
forms a uniform elastomeric body with the covering layer 19, the
thickness of the covering layer 19 being gradually reduced, from
the joint interstice 20 in the direction of the roadway surface 5a.
At the point 21, the metal plate 8 defines the top of the groove 13
and at the point 22 the metal mounting 9 defines the bottom of the
groove 13. The metal plate 8 and the metal mounting 9 are
advantageously covered, in the vicinity of the points 21 or 22 and
as is also the entire upper surface of the metal parts adjoining
the groove, with a further elastomeric layer. For facilitating
securing of the lateral fixture members 23 of the expansion body 4,
the aperture 13a of the groove 13 is defined by parts made of
elastomeric material on both sides, the upper projection 24 being
formed by part of the intermediate layer 10 and the lower
projection 25 by a separate application of elastomeric material on
the metal mounting 9.
The right-hand joint margin according to FIG. 3 shows a section,
taken along the line specified as R--R in FIG. 4. In the section of
the left-hand joint margin shown in FIG. 3, an anchor bolt 26 is
shown, on which the metal mounting 9 is firmly secured by means of
nut 27 which is accessible from above. The nut 27 is disposed in a
bore 28 in the marginal body and, in the vicinity thereof, the
metal plate 8 comprises a recess 29, as illustrated in FIG. 4 by
dash lines.
FIG. 5 shows a part of the combined metal plate 8 and metal
mounting 9, apertures 30 being provided in the metal plate. Owing
to these interruptions 30, the connection between the covering
layer 19 or intermediate layer 10 and the metal parts is
improved.
The metal parts of the construction, that is, the metal plate and
metal mounting, can be produced by extrusion; the combination of
metal plate and metal mounting into one member is particularly
advantageous. The metal parts can also be produced from a one-piece
hollow sheet metal profile by stamping and bending of strips,
extending transversally relative to the longitudinal sense
thereof.
Transport and mounting of the construction can be substantially
simplified in that the metal members consist of short part-members,
disposed in closely adjacent arrangement in the longitudinal sense.
Thus the marginal member can be wound into rolls and transported.
Owing to the flexibility, which is thus attained, it can be more
easily handled during mounting operations and more easily adapted
to irregularities during assembly. According to the dimensions
selected in each case for engagement of the part-members made of
metal and the sections of rubber which are formed between them,
varying lengths of the marginal bodies can be detached, with the
appropriate graduation, from a longer piece, in a simple
manner.
* * * * *