Note: Descriptions are shown in the official language in which they were submitted.
1337634
An insulating structure
The present invention relates to an insulating structure
which can be used to prevent soil from freezing to an extent such
as to cause so-called frost damage, and also for other insulating
purposes, e.g. in roof insulations, and which comprises two sec-
tions, each including a plurality of mutually adjacent insulating
slabs or sheets.
It is well known that in order for soil to freeze such as
to cause damage to objects in the proximity thereof, it is
necessary for water to be present in the soil and for the soil
to be subjected to frost. It is also known that such frost
damage can be prevented or avoided, by preventing frost from
penetrating to water-containing regions of the soil by draining
such regions and/or by preventing the passage of water thereto.
Different drainage methods and different methods of replacing
impervious mass, e.g. rock down to frost free depths are used to
this end. With regard to roads, highways, etc., the road pave-
ment structure includes a sub-base which forms the lowermost
layer of the road pavement structure and which normally consists
of gravel-like or sand-like material. Due inter alia to its low
capillarity, this layer will prevent the transport of water from
the road sub-structure to the upper layer of the pavement
structure and will reduce the bearing capacity of the road and
increase the risk of frost damage thereto. The thickness of the
sub-base varies in dependence on just how prone the road sub-
structure is to frost damage, and in unfavourable circumstances
may in each case reach one meter. Although these safety measures
make it difficult for water to penetrate to the pavement struc-
ture, frost damage nevertheless often occurs, and consequently
various methods have been tried to stop or to reduce frost
penetration into the road sub-structure, with the aid of various
kinds of
I 33 7634
_ 2
insulating layer. One example of such known frost damage
eliminating layers is found disclosed in Swedish Patent
Specification 342 276.
In recent times ground insulation intended for preventing
frost damage to walls, building foundations, courtyards,
parking lots and like structures has comprised almost exclu-
sively of cellular plastic insulating slabs or blocks which
are laid out manually, edge to edge and one at a time on a
smooth bed of sand. In order to prevent the slabs from
sliding apart, pegs or stakes are normally driven into the
ground, through the slabs in`the outer rows and sand is
often heaped on the slabs as they are laid out, in order to-
prevent the slabs from moving in relation to one another
during subseq~uent working operations. The task of laying out
the slabs by hand is both laborious and time consuming, and
thus a very expensive method of providing protection against
frost damage. Furthermore, it is difficult to achieve and
maintain tight abutment between mutually adjacent slabs,
even after applying the pavement structure material; instead
the slabs as a rule, are moved apart by the pavement
material as it is applied, so as to form gaps through which
frost can penetrate down into the sub-structure and water
can penetrate from underlying ground up into the pavement
structure.
Another factor which adds to the cost of this type of insu-
lation lies in the fact that the cellular plastic used in
the insulating slabs must be water repellent, which means
that a relatively expensive plastic must be used, e.g. an
extruded styrene cellular plastic having a bulk density of
40 kg/m3.
Consequently, an object of this invention is to provide an
insulating structure which will function effectively as a
protection against frost and which is also well suited for
..~
_n '
` 1337634
other insulating purposes, e.g. as roof insulation,and which
can be readily laid out and placed in position without risk-
ing the occur~ence of thermal bridges or water permeable
spaces or gaps in the laid insulation. Furthermore, when
required or if so desired, it should be possible to use sub-
stantially cheaper material in the insulating structure than
was hitherto possible in the construction of an effeçtive
protection against frost.
This object is achieved with the inventive insulating struc-
ture having the characterizing features set forth in the
characterizing clauses of the following claims.
The invention is described in more detail hereinafter with
reference to the accompanying drawings, in which Figure l is
a perspective view of one embodiment of the inventive insu-
- lating structure; Figure 2 is a sectional view in larger
scale taken essentially on the line II-II in Figure l;
Figure 3 is a perspective view of a supplementary element
which is complementary to the Figure l embodiment and which
is effective in the construction of a double layer of insu-
lation; Figure'4 is a sectional view of an insulating struc-
ture incorporating the supplementary element; Figure 5 is a
perspective view of an alternative embodiment of the inven-
tive insulating structure; Figure 6 is a perspective view ofan upper or lower part of this latter embodiment; Figure 7
is a perspective view of this latter structure part when
folded-up and ready to be packaged, transported and laid
out; Figure 8 is a perspective view of a folded intermediate
part of the embodiment illustrated in Figures 5 and 6;
Figures 9 and lO illustrate a hinged configuration of a part
of the inventive insulating structure and show the part in a
flat state and in an angled state respectively; Figure ll
illustrates a hinged configuration of the upper part of the
Figure l embodiment and shows said upper part when angled;
Figure 12 is a longitudinal sectional view of a tapering
__
- 1337634
embodiment of the present invention; Figure 13 illustrates
laying of the inventive insulating structure; and Figure 14
illustrates the use of the hinged embodiment illustrated in
Figure 11.
The inventive insulating structure, which can be used to
eliminate the risk of soil freezing or for other insulating
purposes, includes at least one base section 1 and a top
section 2, each of which has a mat-like configuration and
can be produced in any desired length. Each such section 1,
2 includes a respective carrier foil 3 and 4 made of water-
impermeable plastics material, and a plurality of mutually
adjacent insulating slabs 5 and 6, the numbers of which
correspond to the lengths of respective carrier foils and
which are bonded to said foils, e.g. as by gluing or stap-
ling. The foils may cover the slabs 5 and 6, either comple-
tely or partially, and may also be made wider than the
slabs, as illustrated by the chain line 7 in Figure 1.
The interspacing of the slabs 5 in the base section 1 is
determined by the widths of the slabs 6 in the top section
2, such- that the slabs 6 of the top section will fit into
the spaces 8 between respective slabs of the base section 1,
and vice versa. Thus, when the top section 1 is placed on
top of and fitted to the base section 2, there is formed an
integratd insulating layer which exhibits no thermal bridges
and which is protected against moisture and water penetra-
tion from both beneath and above the foil coverings 3, 4 of
the two sections.
When the insulating slabs of both the top and bottom sec-
tions 1, 2 are composed of an insulating material which is
water repellent in itself, e.g. extruded styrene cellulose
plastic having a bulk density from 30-40 kg/m3, there can
be used in principle, a foil material which is moisture per-
meable. Neither need the foil cover the insulating slabs
/~ .
133763~
completely, since in this case it suffices for the foil to
cover said slabs solely to an extent at which said foil will
function as a carrier for the slabs of respective sections
and fixate the mutual positions of said slabs, in the inten-
ded manner.
The slabs 4, 5 of both the top and base section of theinventive insulating structure have a trapezoidal cross-sec-
tional shape, which is advantageous for the reason that a
wedge effect is achieved between the slabs 4, 5 of said sec-
tions and therewith a sealing interface abutment there-
between, and also because the foil in both the top section
and the base section will be stretched at the same time as
the base section slabs 4 are mutually locked in a manner
which is so effective as to enable the slabs to take-up
loads exerted both from above and from beneath, e.g. frost
heave, without appreciable movement between the slabs. Natu-
rally, the slabs 5, 6 of respective sections may have cross-
sectional shapes other than that illustrated, e.g. a rec-
tangular cross-section, although the illustrated cross-sec-
tion is preferred because of the wedging and locking effect
obtained betwe'en :the top and base sections l, 2 when the
insulating structure is under load.
The insulating slabs 6 of the top section 1 may have the
same width as the plates 5 of the base section 2, in the
case shown in Figures 5-7, or may be wider than said slabs
5. As a rule, however, the top section slabs 5 will be
narrower than the base section slabs, as in the càse of the
Figures 1 and 2 embodiment in which the top section slabs
have a bar or strip shape and which may even have a width
smaller than twice the slab thickness. When the width of the
slab surface remote from the foil, and therewith a spacing
between the slabs 5, 6 adjacent the foils 3 and 4 respecti-
vely, is at least equal to twice the slab thickness, ahighly advantageous construction is obtained which enables
.;~
~ ~ 6 133763~
each insulating mat or section 1, 2 to be packaged with res-
pective slabs 5, 6 in mutual abutment, as illustrated in
Figures 7 and 8, and even vacuumed packed in an envelope
(not shown), in a moisture proof fashion when the need
arises, whereby the package obtains the smallest possible
volume, which is of important benefit with regard to
transportation, while enabling the sections, or mats, to be
withdrawn readily from their respective packages and laid
directly on the intended foundation surface.
In the case of the Figure 5-7 embodiment, the base section 1
and the top section 2 correspond to one another, as is illu-
strated in Figures 6 and 7 by the inclusion of bracketed
reference numerals corresponding to the top section 2.
In accordance with the concepts fundamental to the inven-
tion, the inventive insulating structure may include at
least one interlay or complementary section 9, as illustra-
ted in Figure 3 and Figure 4, by means of which the insula-
ting thickness of the insulating structure can be doubled.Obviously, this thickness can be trippled, etc., by inclu-
ding a further interlay 9, or further interlays.
The interlay illustrated in Figure 3 belongs to the embodi-
ment illustrated in Figures 1 and 2 and includes a carrier
foil lO, which need not necessarily be moisture proof, with
one side of the foil joined to insulating slabs 11 which
correspond exactly to the slabs 6 of the top section 2, and
with the opposite side of the foil joined to insulating
slabs 12, which correspond exactly to the slabs of the base
section 1, the slabs 11, 12 on both sides of the foil 10 of
said interlay 9 being joined mutually with the foil 10 so
that the longitudinal centre lines of said slabs mutually
coincide or lie in one and the same plane at right angles to
said foil 10.
1337634
Figure 4 is a sectional view showing an insulating structure
according to the Figure 1 and 2 embodiment laid on a founda-
tion surface and incorporating an interlay 9, with the bar-
like slabs 11 of said interlay located between the base sec-
tion slabs 5 and the insulating slabs 12 of said interlaylocated between the bar-like insulating slabs 6 of the top
section. The aforesaid interlocking effect between the slabs
of the various sections is also obtained in this case.
Figure 8 illustrates an interlay for the embodiment of
Figures 5 and 6 in a folded state, in order to show that
such interlays can also be packaged with their respective
insulating slabs in mutual abutment, when the distance
between the slabs is at least equal to twice the slab
thickness.
In accordance with the concept of this invention, the base
section 1 and the top section 2 can be hinged with their
respective foils 3 and 4 serving as hinge means (Figures
9-11), by dividing each individual slab located on a foil 3,
4 into two parts (cutting through said slabs) in one and the
same longitudihally extending plane 13, or by arranging two
slabs 5 and two slabs 6 in respective edge-to-edge abutment,
with the mutually opposing edges of respective slabs being
left free from one another and lying in said common plane
13. Such a hinged part 1, 2 can thus be swung through 180
in one direction. A hinged base section 1 can be used, for
instance, for insulating both side surfaces of a corner
structure, wherewith if the one corner surfàce is vertical,
a top section associated with said base section can be
nailed, stapled or glued to the base section part which
covers the vertical surface.
In the case of ground insulation in particular, it is
sometimes desired to taper the insulating layer down to
zero. An embodiment to this end is illustrated in Figure 12.
-
~ 8 1337634
In the case of this embodiment, the base section slabs 5have decreased thickness in a direction towards one end of
the insulating structure, as do also the slabs 6 of the top
section, wherewith each such slab 6 decreases in thickness
in its transverse direction, either continuously or dis-
continuously, with a total reduction in thickness corres-
ponding to the difference in thickness between two mutually
adjacent slabs 5 in the base section 1. In the case of the
Figure 12 embodiment the decrease in thickness of the slabs
6 in the top section is discontinuous.
Figures 13 and 14 illustrate the orientation of inventive
insulating structures in forming a frost protector in a road
construction. This frost protector or insulating structure
is formed by first placing a plurality of base sections 1 in
mutually adjacent relationship, with the plastic layer 3
towards a well smoothed, previously prepared bed 15 of sand
or like material. Top sections 2 are then placed on the base
sections 1, while ensuring that each top section 2 extends
over two mutually adjacent base sections 1, such as to cover
the join 16 between two base sections, the edge parts being
covered by top sections 2 of corresponding widths, e.g. half
the normal width. In order to avoid the occurrence of an
opening between two top sections 2 or between two base sec-
tions 1, the respective foils 4 and 3 of said sections can
- be caused to extend somewhat beyond the one`end edge of the
slabs, such as to form flaps 7 (see also Figure 1) which
overlap the foils 5 and 6 of respective adjacent sections.
The end surfaces of the slabs can be coated with a water
repelling material, so as to prevent the ingress of moisture
into said edges.
Subsequent to laying out a sufficient number of top and
bottom sections 1 and 2 to cover the area intended, a mate-
rial filling 17 can be applied to the top of the resultant
insulating structure formed by surface laid sections 1, 2,
whereby the sections 1, 2 are compressed to form an imper-
- ,~.~
~ ` 9 1337634
vio`us, coherent insulating structure, while at the same time
the plastic layers 3, 4 on the upper and lower surfaces of
the insulation prevent water from coming into contact with
the insulating slabs 5, 6, both from beneath and from above,
and also from penetrating through the insulation to the
pavement structure of said road.
Figure 14 illustrates one aspect of use of the hinged embo-
diment of a top section according to Figure 1, this aspect
being particularly suitable in those instances when one half
18 of the road is to be traffic bound and the other half 19
is to be closed while repairs are carried out thereon. In
this case, the slabs 6 in the top section 2 are divided cen-
trally, wherewith the plastic layer 4 functions as a hinge
means which enables one~half of the top section 2 to be fol-
ded up against the edge 20 of the traffic bound road half
18, where it serves as a partition wall between the traffic
- bound road surface 18 and the filling 21 placed on top of
the laid-out insulating structure 1,2 in the road half 19
under repair or construction. When repair to this half of
the road has been completed and can again carry traffic, the
other road half 18 is dug up and after laying out base sec-
tions 1, the upstanding part of the top section 2 in Figure
14 is swung down onto the nearest adjacent base section, so
as also to obtain therewith effective sealing of the insula-
ting structure at the junction between the two road halves.
The present invention enables an insulating structure to be
constructed very rapidly, without risk`of the slabs included
in said structure sliding apart, and also enables, when
desired, the insulating plates to be protected against
moisture both from beneath and from above. In such cases,
the slabs may also be comprised of a substantially cheaper
plastics material than was hitherto possible for ground
insulating purposes.
. ~
~ lO 1337634
It'will be understood that the present invention is not
limited to the aforedescribed and illustrated embodiments,
and that various modifications and changes can be made
within the scope of the invention defined in the following
claims.
For example, materials other than plastic materials can be
used in the layer serving to carry the insulating slabs.
When the insulating structure is to be used to insulate
roofs, the carrier layer 4 of the top section may comprise
tar paper or some other suitable roof covering. In other
words, the carrier layers can~be adapted to their intended
environments and to their particularly intended purposes. In
those instances when the top sections, base sections and!or
interlays cannot be stacked with respective slabs lying on
or adjacent one another, each such section or interlay can
be rolled up and packaged in a tubular wrapper, sleeve or
the like.
SA
''~''''' -
