[0001] The present invention relates to a method for renovation of surface dressings around
well curbs, and a compressible device for use in the method according to the present
invention.
[0002] Ordinary wells or shafts, e.g. wells that are a part of a sewerage system, surmounts
upwards with a curb and a cover. Within the scope of the present invention the term
"well curb" is to be understood as a curb, which is a a part of covering of a well,
shaft or the like.
[0003] A well-known way of fitting is to place the lower edge of the well curb on the top
edge of the well or shaft, in such a way that the well is carrying the majority or
all of the weight of the curb and cover. The surface dressing, e.g. ordinary road
surfaces as asphalt, is in this case not directly connected to the well curb.
[0004] It is a well-known phenomenon that surface dressings, especially road surfaces as
asphalt or bituminous surfaces, settle over time. This is in particular the case for
the area between the curb and the road surface where weather exposure as temperature
based expansions and contractions has a far more large effect than with the continuous
road surface. It is thus a drawback of the above method that the road, which is not
connected to the curb, will settle and thus the curb will extend over road level.
[0005] In some cases the well curb is positioned with a clearance in the related well or
shaft. These well curbs will in the following be referred to as floating well curbs.
[0006] Well curbs of the floating kind avoid the above problem in that these are connected
to or are resting on the actual road surface. On the other hand such a floating curb
is not connected to the well. The main part or the entire weight of the curb is thus
carried by the road or road surface. This means that the curb will sink or level together
with the road surface. Despite this advantage it is still necessary to renovate the
road surface around the well curb regularly as the asphalt around the well curb still
will settle.
[0007] The area around the well curb is typically renovated by lifting the well curb, whereafter
all material, which has settled around the opening in the road surface, e.g. asphalt,
is removed. Hereafter an installation frame is positioned where the well curb will
be lying afterwards. The excavated area is filled with new asphalt and then the installation
frame is removed and the well curb is positioned. The well curb might be rolled into
the covering layer. The disadvantage of this method is that it is time consuming and
costly. Furthermore, the problems with settling will return and thus it will be necessary
to perform this type of renovation regularly.
[0008] It is thus a first aspect of the present invention to provide a method of the kind
mentioned in the opening paragraph whereby it is possible faster and easier to renovate
surface dressings around well curbs.
[0009] In a second aspect according to the present invention a method is provided of the
kind mentioned in the opening paragraph whereby it is possible to lower the expenses
related to renovation of surface dressings significantly.
[0010] In a third aspect according to the present invention is provided a compressible device,
which facilitates the method according to the present invention.
[0011] The new and unique whereby this is achieved according to the present invention consist
in that a method is provided for renovation of surface dressings around well curbs,
where the method comprises a lifting of the well curb to a first position, placement
of a compressible device around the well curb, lowering of the well curb to a second
position so that the compressible device is abutting an upper edge of a well, injection
of a casting material into the cavity between the surface dressing and a filling around
the well, and lowering of the well curb to a final third position.
[0012] In a preferred embodiment the method according to the present invention is used for
renovation of surface dressings around floating well curbs.
[0013] To ensure that no material spills into the well a collector may be mounted in the
upper part of the well before the method according to the present invention is initiated.
[0014] The existing curb is raised to a first position, e.g. by use of a suited lifting
device, which secures that the surface dressing around the curb is not damaged or
looses stability. The curb may then, if necessary, be cleaned of remains of surface
dressing or rust. Similarly, the existing surface dressing can be cleaned of loose
flakes or other removable material. This can for example be done by use of a pneumatic
chisel or by compressed air. If the surface dressing is wet it can be dried by an
appropriate device, e.g. a gas burner.
[0015] In the curb's first position a compressible device is positioned around the curb.
The compressible device can e.g. be a ring or a frame of foam rubber. It is important
that the shape of the compressible device fits the concerned curb, i.e. if it is a
curb with a circular cross section a ring-shaped compressible device is used. If on
the other hand it is a curb with a square cross section a square-frame-shaped compressible
device is used.
[0016] The object of the compressible device is to ensure a packing between the curb and
the upper edge of the well. By means of this packing it is avoided that casting material
floats into the well. A further advantage is found in that the compressible device
prevents that the curb is cast to the upper edge of the well.
[0017] The curb with the positioned compressible device is then lowered to a second position
so that the compressible device is abutting the upper edge of the well. Said second
position can for example be around 20 mm above the surface level, e.g. the road level.
In this example the upper edge of the curb will thus project 20 mm above the road
level. In this position a casting material is injected into the cavity between the
surface dressing and the filling around the well.
[0018] I a particularly advantageously embodiment the casting material is liquid, e.g. a
liquid asphalt based composition.
[0019] The curb is thus lowered to a permanent third position, which is the same as the
final port-renovation-position. This further lowering is possible even though the
compressible device already is abutting the upper edge of the well, because the device
around the well curb is compressible. The curb is kept in this position until the
casting material has hardened. Hereafter the lifting device can be dismounted. Excess
casting material may be removed and the transition between the surface and the renovated
area may if necessary be applied a suitable hardening agent.
[0020] An advantage of the method according to the present embodiment is that a full depositing
between the surface, e.g. asphalt, and the well curb is ensured. Furthermore, the
method results in that the existing surface, e.g. roadway, is maintained around the
well curb, which prevents subsequent settlements of the area. The method according
to the present invention is significantly faster than already known renovation methods.
[0021] It is emphasized that there is made no or very small demands to the long-term durability
of the compressible device. As soon as the casting material has hardened the compressible
device has fulfilled its function. This means that the intended function is not to
carry the curb. In principle the compressible device according to the present invention
can thus be made of a biologically degradable material.
[0022] According to an embodiment of the method according to the present invention, the
compressible device is a ring or a frame, which is made of a material comprising at
least one natural or synthetic polymer. Considered polymers comprise rubber, foam
rubber, butyl rubber, silicone rubber, poly butadiene, poly isobutylene, polyurethane
and polyurethane foam.
[0023] According to another embodiment of the method according to the present invention
the compressible device is inflatable. This can be implemented by means of a ring
or a tube, which can be inflated by compressed air or by a fluid.
[0024] According to yet another embodiment of the method according to the present invention
the casting material comprises an asphalt based composition, e.g. the asphalt for
repairing "Vergumix Super Mak" from the company Vergutech Scandinavien, Digemosevej
1, DK-4340 Tølløse.
[0025] According to another embodiment of the method according to the present invention
the lifting and lowering of the well curb is done by means of a lifting apparatus,
e.g. the hydraulic well curb lifting device "MSRH-50" from the company Hans Joch Machinenbau
GmbH, Reiffeisenstrasse 63, D-74906 Bad Rappenau, Germany.
[0026] The present invention further comprises a compressible device for positioning around
a well curb by the method according to the present invention.
[0027] In a preferred embodiment this device is a ring or a frame, made of a material comprising
at least one natural or synthetic polymer.
[0028] In another embodiment the compressible device according to the present invention
is inflatable.
[0029] In another embodiment the compressible device according to the present invention
comprises at least one biologically degradable material.
[0030] The invention will be described below with reference to the drawing where
Fig. 1 shows a cross section of an area around a well curb of the floating kind,
fig. 2 shows a cross section through an area around a well curb of the floating kind
where the area needs renovation
fig. 3 shows a cross section through an area around a well curb of the floating kind
where the area needs renovation and where the well curb has been elevated to a first
position,
fig. 4 shows a cross section through an area around a well curb of the floating kind
where the area needs renovation and where the well curb has been lowered to a second
position, and
fig. 5 shows a cross section through an area around a well curb Of the floating kind
where the area has been renovated and the well curb has been lowered to the final
third position.
[0031] The area 1 around a well curb 2 of the floating kind, as shown in figure 1, comprises
a well curb 2 with a matching cover 3. Furthermore a surface dressing 4 is shown,
e.g. a road layer as asphalt, which defines a surface level 11. In the surface dressing
4 is an opening 5, which e.g. is shaped as a circular opening. The well curb 2 has
a flange 6 resting on the surface dressing 4. The well curb 2's lower part 7, which
for example can be shaped as a cylindrical casing, is introduced through opening 5
into an opening 8 of a well 9. The opening 8 can e.g. have a circular cross section.
Around the well 9 is formed a filling 17. The filling 17 is surrounded by soil 19.
Below the surface dressing 4 is a base 18. Between the outer side of the well curb
2's lower part 7 and the well opening 8's inner side 15 is a air gap 10 which cause
the well curb 2 to hang or "float" freely. The air gap 10 can e.g. be ring shaped.
[0032] Figure 2 shows a situation where the well curb 2's upper edge has sunk below the
original surface level 11 of the surface dressing 4. This is due to settling and/or
erosion of the surface dressing 4. It is surface dressings 4 in such a condition that
need renovation by means of the method according to the present invention.
[0033] Figure 3, shows the same area as in figure 2. The difference is that the well curb
2 in figure 3 has been lifted up to a first position which allows the placement of
a compressible device 12 around the well curb 2's lower part 7. The lifting can for
example be carried out by means of a suitable machine (not shown). The compressible
device 12 can e.g. be a rubber foam ring. The compressible device 12 can e.g. be shaped
and positioned in such a way that it is abutting the well 9's upper edge 13 when the
well curb 2 is lowered to the second position, as shown in figure 4. The lowering
is e.g. carried out by a suitable machine.
[0034] In figure 4 the compressible device 12 is as mentioned abutting the well 9's upper
edge 13 (the upper edge is shown in the Figures 1 - 3) which permits injection of
a casting material 14 (shown in figure 5) into the cavity 16 between the surface dressing
4 and the filling 17 around the well 9, without the casting material 14 spills into
the air gap 10 between the outer side of the well curb 2's lower part 7 and the well
opening 8's inner side 15. At the same time the vertical level of the well curb 2
is a little above its final level and than the surface level 11. This makes it easier
to inject the casting material 14. The thickness of the compressible device 12 is
sufficient to cover the border area between the well 9's upper edge 13 and the surrounding
filling 17. Hereby it is avoided that the well curb 2 is cast to the well 9's upper
edge 13.
[0035] The last step in the method according to the present invention is shown in figure
5. The well curb 2 is lowered to its final position, which equals the original position
shown in figure 1. The well curb is still carried by e.g. a machine (not shown), until
the casting material 14 has hardened. If the casting material 14 is a fluid material,
as e.g. two component asphalt emulsion, it also implies that the lowering of the well
curb 2 from its second position to its third final position must happen before the
fluid material has hardened. When the well curb 2 is transferred from its second position
to its third position the compressible device 12 is been compressed in its vertical
direction, i.e. upset.
[0036] The area and the method as shown in the figures 1 - 5 are to be regarded as examples
and are not to be construed as limiting the scope of the invention to the shown embodiments
or areas. Even if the well curb 2's flange 6 in figure 5 is resting on the casting
material 14 it could in principle also be that the well curb 2's flange 6 is settled
or rolled into the casting material 14 so that the well curb 2's upper edge is at
the same level as the surface level 11. Similarly it is of course possible that the
renovation area comprises more layers than shown in figures 1 - 5, such as a base
or a wearing course.
1. A method for renovation of surface dressings (4) around well curbs (2) wherein the
method comprises a lifting of the well curb (2) to a first position,
characterized in that the method further comprises
- placement of a compressible device (12) around the well curb (2)
- lowering of the well curb (2) to a second position so that the compressible device
(12) is abutting the upper edge (13) of a well (9)
- injection of a casting material (14) into the cavity (16) between the surface dressing
(4) and a filling (17) around the well (9), and
- lowering of the well curb (2) to a final third position.
2. A method according to claim 1, characterized in that the compressible device (12) is a ring or a frame, which is made of a material comprising
at least one natural or synthetic polymer.
3. A method according to claim 1 or 2, characterized in that, the compressible device (12) is inflatable.
4. A method according to any of the claims 1 - 3, characterized in that the casting material comprises (14) an asphalt-based composition.
5. A method according to any of the claims 1 - 4, characterized in that the lifting and lowering of the well curb is done by means of a lifting apparatus.
6. A compressible device (12) for positioning around a well curb (2) be means of the
method according to any of the preceding claims 1 - 5.
7. A compressible device (12) according to claim 6, characterized in that the device (12) is a ring or a frame made of a material comprising at least a natural
or synthetic polymer.
8. A compressible device (12) according to claim 6 or 7, characterized in that the device is inflatable.
9. A compressible device (12) according to claim 6 or 8, characterized in that the device comprises at least one biologically degradable material.