[0001] The invention relates to a gantry for spanning a road, for example in connection
with the presentation of information to users of the road, which gantry comprises
a lattice girder, which is constructed of at least one uppermost longitudinal element,
a lowermost longitudinal element and lattice elements interconnecting these longitudinal
elements, and, at each end of this lattice girder, a pair of upwardly converging legs.
[0002] Gantries of this kind are commonly known and are used for the attachment of billboards
and/or traffic-lane signalling. The known gantries are produced from steel and are
consequently very heavy. Moreover, the fastening of the girder to the legs is labour-intensive,
so that the installation of the gantry causes a great deal of traffic obstruction.
[0003] The object of the invention is to provide a gantry which does not have this drawback.
This object is achieved by the fact that the uppermost longitudinal element passes
over each pair of legs and is supported there by means of a bearing structure.
[0004] In such a construction, once the legs have been installed, the girder is able to
be directly supported in a stable manner on the bearing structure. In order to obtain
this stable bearing structure, there is no need to fit bolt connections directly.
As soon as the girder is installed, the crane truck can already be removed; the bolt
connections can then be fitted. The advantage of this is that the traffic is only
very briefly obstructed by the operations connected with the installation of the girder.
[0005] It is known to use a three-dimensional lattice girder, the cross-section of which
is triangular and has the apex directed downward, and the uppermost longitudinal element
of which comprises two parallel structural parts interconnected by horizontal lattice
elements. According to the invention, in this construction the two uppermost parallel
structural parts pass over each pair of legs and are each supported there by means
of a bearing structure.
[0006] In order to increase the stability of the support afforded to the girder, each pair
of legs has, above the spot where they are fastened together, an outwardly protruding
bearing structure, the width of which is approximately equal to the width of the uppermost
longitudinal element. Preferably, in that connection, the legs of each pair each have
an obliquely upward running extension piece, directed away from the extension piece
of the other leg, and the extremities of the extension pieces are each provided with
a bearing structure for the uppermost longitudinal element.
[0007] The structure of the gantry according to the invention is particularly suitable for
aluminium construction. To this end, the uppermost longitudinal element comprises
two parallel aluminium longitudinal profiles, which longitudinal profiles each possess
a flat surface on their side facing the lattice elements.
[0008] In addition, the longitudinal profiles can possess two flat base surfaces, which,
in transverse section, enclose an angle which is approximately equal to the complement
of the base angle of the triangle, which base angle is determined by that longitudinal
profile. The lattice elements, which can equally consist of aluminium tubes, then
need to be obliquely pared in one direction only, thereby making the girder easier
to produce.
[0009] Each longitudinal profile can further possess two flat side surfaces, which are each
connected at right-angles to a base surface and are interconnected. The support afforded
to the girder can be made very stable if each bearing structure has an obliquely upward
running flange, the side surfaces of the longitudinal profiles facing away from each
other being shut in between the associated flanges at each end of the girder.
[0010] According to a preferred embodiment, the side surfaces of each longitudinal profile
are interconnected by a curved surface and that curved surface is connected by means
of an internal partition to both base surfaces. A longitudinal profile which is made
in this way is extremely resistant to the compression forces to which it is exposed;
moreover, the internal partition helps the gradual transmission of forces between
the longitudinal profile and the lattice elements.
[0011] The legs of each pair can each carry a U-shaped fastening piece, these fastening
pieces being interconnected. These fastening pieces can be identical and asymmetrical.
[0012] The legs and the fastening pieces can also be made of aluminium. In that case, the
legs comprise a plurality of interconnected longitudinal segments.
[0013] The invention will be explained in greater detail below with reference to the figures,
in which:
[0014]
- Figure 1
- shows a perspective view of the gantry according to the invention
- Figure 2
- shows an enlarged detail of Figure 1,
- Figure 3
- shows an alternative detail,
- Figure 4
- shows a diagrammatic transverse section through the girder of the gantry,
- Figure 5
- shows a transverse section through a pair of legs,
- Figures 6a and 6b
- show a detail of the girder.
[0015] The gantry which is shown in Figure 1 comprises a girder 1 which is supported at
both ends by a pair of legs 2, 3. The girder comprises two uppermost longitudinal
profiles 4, 5, a lowermost longitudinal profile 6 and lattice profiles 7 which interconnect
these longitudinal profiles.
[0016] As illustrated in Figures 2, 3 and 5, the legs 2, 3 comprise, on their mutually facing
sides, a U-shaped stirrup 8, which stirrups are identical and are fastened together
by a plurality of bolts 9. In addition, the legs comprise extension pieces 10, 11
which are directed obliquely upward away from each other and on which the longitudinal
profiles 4, 5 of the girder 1 are supported.
[0017] The cross-section of Figure 4 illustrates the longitudinal profiles 4, 5, 6. These
all comprise two flat base surfaces 12, 13, to which the lattice profiles 7 are welded.
At the same time, they each comprise two flat side surfaces 14, 15, which are joined
together by a curved surface 16. The curved surfaces are each connected by an internal
partition 17 to the flat base surfaces 13, 14.
[0018] As can be seen in Figure 5, the legs are made up of longitudinal segments which are
welded together by means of fastening strips 20, 21. These segments are also welded
together at the site of the joints 22.
[0019] In Figures 6a and 6b, it can be seen that the lowermost longitudinal profile 6, in
the variant of Fig. 3, supports a cable duct 18 by means of a flange 19. The cable
duct is provided with a cover 20, which can be swung open to one side. The flange
19 has two strips 21 by which it is fixed to the lowermost longitudinal profile 6.
[0020] The duct 18 and flange 19 are likewise illustrated in Figure 3. Here it is also evident
that the cables are able to be conducted downward via an elbow piece 22.
1. Gantry for spanning a road, for example in connection with the presentation of information
to users of the road, which gantry comprises a lattice girder, which is constructed
of at least one uppermost longitudinal element, a lowermost longitudinal element and
lattice elements interconnecting these longitudinal elements, and, at each end of
this lattice girder, a pair of upwardly converging legs, characterized in that the
uppermost longitudinal element passes over each pair of legs and is supported there
by means of a bearing structure.
2. Gantry according to Claim 1, comprising a three-dimensional lattice girder, the cross-section
of which is triangular and has the apex directed downward and the uppermost longitudinal
element of which comprises two parallel structural parts interconnected by horizontal
lattice elements, the two uppermost parallel structural parts running on over each
pair of legs and being each supported there by means of a bearing structure.
3. Gantry according to Claim 2, in which each pair of legs has, above the spot where
they are fastened together, an outwardly protruding bearing structure, the width of
which is approximately equal to the width of the uppermost longitudinal element.
4. Gantry according to Claim 3, in which each of the legs of each pair has an obliquely
upward running extension piece, directed away from the extension piece of the other
leg, and the extremities of the extension pieces are each provided with a bearing
structure for the uppermost longitudinal element.
5. Gantry according to Claim 4, in which the uppermost longitudinal element comprises
two parallel aluminium longitudinal profiles, which longitudinal profiles each possess
a flat surface on their side facing the lattice elements.
6. Gantry according to Claim 5, in which the longitudinal profiles possess two flat base
surfaces which, in transverse section, enclose an angle which is approximately equal
to the complement of the base angle of the triangle, which base angle is determined
by that longitudinal profile.
7. Gantry according to Claim 6, in which each longitudinal profile possesses two flat
side surfaces which are each connected at right-angles to a base surface and are interconnected.
8. Gantry according to Claim 7, in which each bearing structure has an obliquely upward
running flange, the side surfaces of the longitudinal profiles facing away from each
other being shut in between the associated flanges at each end of the girder.
9. Gantry according to Claim 7 or 8, in which the side surfaces of each longitudinal
profile are interconnected by a curved surface and that curved surface is connected
by means of an internal partition to both base surfaces.
10. Gantry according to one of Claims 4-9, in which the legs of each pair each carry a
U-shaped fastening piece, these fastening pieces being interconnected.
11. Gantry according to Claim 10, in which the fastening pieces are identical and asymmetrical.
12. Gantry according to Claim 10 or 11, in which the legs and the fastening pieces are
made of aluminium.
13. Gantry according to Claim 12, in which the legs comprise a plurality of interconnected
longitudinal segments.