U.S. patent application number 16/534462 was filed with the patent office on 2020-03-05 for uncoupling mat.
The applicant listed for this patent is Werner Schluter. Invention is credited to Werner Schluter.
Application Number | 20200071941 16/534462 |
Document ID | / |
Family ID | 61002853 |
Filed Date | 2020-03-05 |
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United States Patent
Application |
20200071941 |
Kind Code |
A1 |
Schluter; Werner |
March 5, 2020 |
Uncoupling Mat
Abstract
An uncoupling mat includes a flexible plastic layer (2) made of
film-like plastic with structuring that defines indentations (6)
provided with undercuts (5) on the first side (4) and cavities (8)
positioned between the indentations (6) on the opposite second side
(7). A fleece or fabric (3) is securely connected to the second
side (7) and covers the cavities (8). A cross-section of the
indentations (6) in at least some corner regions (10) increases
towards the first side (4).
Inventors: |
Schluter; Werner; (Iserlohn,
DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Schluter; Werner |
Iserlohn |
|
DE |
|
|
Family ID: |
61002853 |
Appl. No.: |
16/534462 |
Filed: |
August 7, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
15914223 |
Mar 7, 2018 |
|
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|
16534462 |
|
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
E04F 15/185 20130101;
E04C 2/20 20130101; E04C 2/32 20130101; E04F 15/182 20130101; E04F
15/186 20130101 |
International
Class: |
E04F 15/18 20060101
E04F015/18; E04C 2/32 20060101 E04C002/32; E04C 2/20 20060101
E04C002/20 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 9, 2017 |
DE |
202017101349.9 |
Claims
1. An uncoupling mat (1) comprising: a flexible plastic layer (2)
made of film-like plastic with structuring that defines
indentations (6) provided with undercuts (5) on the first side (4)
and cavities (8) positioned between the indentations (6) on the
opposite second side (7), and a fleece or fabric (3) securely
connected to the second side (7) and covering the cavities (8),
wherein a cross-section of the indentations (6) in at least some
corner regions (10) increases towards the first side (4).
2. The uncoupling mat (1) according to claim 1, wherein the
cross-section of the indentations (6) in at least some corner
regions (10) increases constantly towards the first side (4).
3. The uncoupling mat (1) according to claim 1, wherein the
cross-section of the indentations (6) in at least some corner
regions (10) increases constantly towards the first side (4) from
the bottom (11) of the corresponding indentation (6).
4. The uncoupling mat (1) according to claim 1, wherein the plastic
layer (2) is provided with a plurality of weakening zones (12)
which extend continuously between opposing side edges of the
plastic layer (2).
5. The uncoupling mat (1) according to claim 4, wherein in the
weakening zones (12) comprise grooves.
6. The uncoupling mat (1) according to claim 4, wherein the plastic
layer (2) has a substantially constant thickness (d), the thickness
(d) being smaller in the region of the weakening zones (12).
7. The uncoupling mat (1) according to claim 4, wherein at least
some of a first group of weakening zones (12) extend parallel to
one another, said parallel weakening zones extending transversely
to a longitudinal direction of the uncoupling mat (1).
8. The uncoupling mat (1) according to claim 7, wherein at least
some of a second group of weakening zones (12) extend parallel to
one another, the second group of parallel weakening zones crossing
the first group of parallel weakening zones at right angles.
9. The uncoupling mat (1) according to claim 4, wherein the
weakening zones (12) are arranged spaced apart from one another
equally at distances being in the range of from 10 to 100 mm.
10. The uncoupling mat (1) according to claim 9, wherein the
weakening zones (12) are spaced at distances being in the range of
from 10 to 50 mm.
11. The uncoupling mat (1) according to claim 4, wherein the
weakening zones (12) each extend between two rows of indentations
(6).
12. The uncoupling mat (1) according to claim 1, wherein the fleece
of fabric (3) has through holes (13) with a cross-section in the
range of from 0.5 to 1.0 mm.sup.2.
13. The uncoupling mat (1) according to claim 12, wherein the
through holes (13) include a cross-section in the range of from 0.5
to 0.8 mm.sup.2.
14. The uncoupling mat (1) according to claim 1, wherein the
cavities (8) cross one another and define a grid- or net-like
arrangement.
15. The uncoupling mat (1) according to claim 14, wherein the mat
includes 100 to 3000 indentations (6) per square metre.
16. The uncoupling mat (1) according to claim 1, wherein the
indentations (6) cross one another and define a grid- or net-like
arrangement.
17. The uncoupling mat (1) according to claim 16, wherein the mat
includes 100 to 3000 cavities (8) per square metre.
18. The uncoupling mat (1) according to claim 17, wherein the
cavities (8) at least partially have an annular cross-section.
19. The uncoupling mat (1) according to claim 18, wherein the
indentations (6) have a minimum width (B.sub.min) in the range of
from 3 to 20 mm.
20. The uncoupling mat (1) according to claim 1, wherein the
indentations (6) have a minimum width (B.sub.min) in the range of
from 3 to 20 mm and a maximum height (H.sub.max) in the range of
from 2 to 20 mm.
Description
PRIORITY CLAIM
[0001] This application is a continuation of U.S. patent
application Ser. No. 15/914,223, filed Mar. 7, 2018, and claims
priority of and to German Patent Application Serial No. 20 2017 101
349.9, filed Mar. 9, 2017, each of which is hereby incorporated
herein by reference in its entirety for all purposes.
BACKGROUND OF THE INVENTION
[0002] Uncoupling mats are used to uncouple a substrate and a slab
covering laid over the latter in terms of stress such that the
transmission of stresses that develop in particular within the
substrate to the slab covering is prevented. In this manner, the
development of cracks in the slab covering or the detachment of
individual tiles can be prevented.
BRIEF SUMMARY OF THE TECHNOLOGY
[0003] In accordance with one aspect of the invention, an
uncoupling mat is provided that includes a flexible plastic layer
(2) made of film-like plastic with structuring that defines
indentations (6) provided with undercuts (5) on the first side (4)
and cavities (8) positioned between the indentations (6) on the
opposite second side (7). A fleece or fabric (3) can be securely
connected to the second side (7) and can cover the cavities (8). A
cross-section of the indentations (6) in at least some corner
regions (10) increases towards the first side (4).
[0004] In accordance with another aspect of the invention, an
uncoupling mat is provided, including a flexible plastic layer made
of a film-like plastic with structuring that defines indentations
provided with undercuts on the first side and cavities positioned
between the indentations on the opposite second side, and a fleece
or fabric securely connected to the second side and covering the
cavities. The mat can be characterised in that the plastic layer
can be provided with a plurality of weakening zones which extend
continuously between opposing side edges of the plastic layer.
[0005] In accordance with another aspect of the invention, an
uncoupling mat is provided, including a plastic layer made of
film-like plastic with structuring that defines indentations
provided with undercuts on the first side and cavities positioned
between the indentations on the opposite second side, and a fleece
or fabric securely connected to the second side and covering the
cavities, in particular an uncoupling mat according to any of the
preceding claims, characterised in that the cross-section of the
indentations in at least some corner regions increases towards the
first side, in particular increases constantly, preferably from the
bottom of the corresponding indentation.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0006] Further features and advantages of the present invention
become clear from the following description of embodiments of
uncoupling mats according to the invention with reference to the
attached drawings. These show as follows:
[0007] FIG. 1 a schematic perspective partial view of an uncoupling
mat according to a first embodiment of the present invention;
[0008] FIG. 2 an enlarged side view of the portion provided with
reference sign II in FIG. 1 and which shows a weakening zone;
[0009] FIG. 3 a top view of the arrangement shown in FIG. 1;
[0010] FIG. 4 a view similar to FIG. 2, which shows an alternative
embodiment of a weakening zone;
[0011] FIG. 5 a side view of the arrangement shown in FIG. 1 in the
correctly laid state;
[0012] FIG. 6 a schematic top view of an uncoupling mat according
to a second embodiment of the present invention;
[0013] FIG. 7 a cross-sectional view along line VII-VII in FIG. 6,
and
[0014] FIG. 8 a cross-sectional view along line VIII-VIII in FIG.
6.
DETAILED DESCRIPTION OF THE INVENTION
[0015] The present invention relates generally to an uncoupling mat
comprising a flexible plastic layer made of a film-like plastic
with structuring that defines indentations provided with undercuts
on the first side and cavities positioned between the indentations
on the opposite second side, and a fleece or fabric securely
connected to the second side and covering the cavities.
[0016] Uncoupling mats of the type specified are used to uncouple a
substrate and a slab covering laid over the latter in terms of
stress such that the transmission of stresses that develop in
particular within the substrate to the slab covering is prevented.
Thus, the development of cracks in the slab covering or the
detachment of individual tiles can be prevented. For this purpose,
in a first step uncoupling mats are normally fastened to the
substrate using an adhesive that grips in the fleece or fabric. The
adhesive can be, for example, a thin bed mortar, a reaction resin
mortar or the like, reference only being made to thin bed mortar in
the following for the sake of simplicity. In a further step the
slab covering is then laid over the plastic layer of the uncoupling
mat, once again using thin bed mortar, the thin bed mortar
anchoring in the indentations provided with undercuts such as to
form thin bed mortar stilts. In this way a secure connection
between the substrate and the slab covering is achieved overall.
Any stresses that are present within the substrate, caused for
example by the remaining drying and curing process of the
substrate, by the so-called settling of a construction, by
temperature changes due to different thermal expansion coefficients
of the materials used or the like, are then absorbed in the
composite and compensated for by corresponding deformation of the
uncoupling mats so that they can not be transmitted to the slab
covering. The freedom of movement of the uncoupling mat required
for this is provided by the cavities formed on the second side of
the plastic layer. Reference is made in this connection, for
example, to the uncoupling mats described in publications DE 37 01
414 A1 and EP 1 073 813 B2, to the entire disclosure of which
reference is herewith made.
[0017] DE 37 01 414 A1 describes an uncoupling mat, the plastic
layer of which has concertina-like structuring, the indentations
defined on the first side as well as the cavities defined on the
second side being in the form of dovetails, and each extending
parallel to one another. In this way, due to the structure, the
freedom of movement of the uncoupling mat required for the
uncoupling is provided substantially in a direction transverse to
the direction of the extension of the cavities.
[0018] In contrast, on the basis of DE 37 01 414 A1, EP 1 073 813
B2 proposes an uncoupling mat with a plastic layer the structuring
of which has cavities that cross in a grid on the second side and
indentations provided with undercuts and delimited by the cavities
on the first side. With this uncoupling mat therefore, use is not
made of the uncoupling principle brought about by the
concertina-like structuring of the plastic layer described in DE 37
01 414 A1. Rather, in the uncoupling mat described in EP 1 071 813,
one relies upon the extensibility of the film-like plastic to
achieve the uncoupling effect which allows movement of the thin bed
mortar stilts formed in the indentations in the direction of the
cavities with deformation of the plastic layer.
[0019] Fundamentally, it is desirable to further improve the
uncoupling capability of known uncoupling mats.
[0020] Furthermore, it is desirable to improve the clamping of the
lower side of known uncoupling mats which is formed by the fleece
or the fabric with a thin bed mortar.
[0021] In addition, one disadvantage of known uncoupling mats is
that upon filling the indentations with a thin bed mortar, the air
can often not completely escape from the indentations, and so air
inclusions develop which form uncontrolled cavities within the
mortar, and this is not desirable.
[0022] On the basis of this prior art it is an object of the
present invention to devise an uncoupling mat of the type specified
at the start with an alternative structure.
[0023] In order to achieve this object, the present invention
devises an uncoupling mat of the type specified at the start which
is characterised in that the plastic layer is provided with a
plurality of weakening zones which extend continuously between
opposing side edges of the plastic layer. In other words, the
present invention proposes further improving the uncoupling
capability of an uncoupling mat of the type described in EP 1 073
813 B2 by the formation of additional weakening zones. By means of
the weakening zones the plastic layer is given structurally an
additional possibility for movement substantially transversely to
the direction of extension, in particular in a straight line, of
the weakening zones which is supplemented by the freedom of
movement provided by the cavities, as a result of which an
uncoupling mat with clearly improved uncoupling capability is
provided overall.
[0024] The weakening zones are preferably provided in the form of
grooves, the grooves possibly having, for example, a semi-circular,
semi-elliptical or a V-shaped or triangular cross-section. In this
way the uncoupling mat according to the invention can be produced
with a simple structure.
[0025] According to one embodiment of the present invention the
plastic layer has a substantially constant thickness, the thickness
being smaller in the region of the weakening zones. In this way,
targeted weakening of the plastic layer is therefore brought about
not only structurally, but also by a smaller thickness of the
plastic layer in the region of the weakening zones.
[0026] Preferably, a first group of weakening zones extending
parallel to one another is provided, which weakening zones extend
in particular transversely to a longitudinal direction of the
uncoupling mat, for example perpendicular to the longitudinal
direction. If the uncoupling mat is formed longitudinally, i.e.
rectangularly as viewed from above, with a shorter and a longer
side edge, the longitudinal direction advantageously corresponds to
the direction of extension of the longer side edge. In this way
additional uncoupling is provided which compensates for stresses
acting in particular substantially perpendicularly to the direction
of extension of the first group of weakening zones.
[0027] Advantageously, a second group of weakening zones extending
parallel to one another is provided which crosses the first group,
in particular at a right angle. Accordingly, a further additional
uncoupling effect is provided which in particular compensates for
stresses acting substantially perpendicular to the direction of the
extension of the second group of weakening zones. It should be
clear that more than two groups of weakening zones extending
parallel to one another, and which cross one another, may also be
provided.
[0028] Advantageously, the weakening zones are arranged spaced
apart from one another equally, the distances preferably being in
the range of from 10 to 100 mm, in particular in the range of from
10 to 50 mm. It has been shown that these distances have a good
uncoupling effect within the ranges specified.
[0029] Advantageously, the weakening zones each extend between two
rows of indentations, i.e. not through the indentations themselves.
Weakening zones can be formed here between each row of
indentations. Alternatively however, it is also possible to provide
weakening zones, for example, only between every second or third
row of indentations.
[0030] In order to achieve the object specified at the start, the
present invention furthermore devises an uncoupling mat of the type
specified at the start which is characterised in that the fleece or
fabric has through holes with a cross-section in the range of from
0.5 to 1.0 mm.sup.2, in particular in the range of from 0.5 of 0.8
mm.sup.2. Such small through holes with a cross-section within said
range are characterised in that they allow the passage of thin bed
mortar in the conventionally used consistency with the normal
manual contact pressure of the uncoupling mats that is involved
when they are being laid, whereupon the thin bed mortar can not
only grip to the fleece or the fabric, but also behind the latter,
clogging of the cavities that are essential for the uncoupling
effect with thin bed mortar being reliably avoided however.
[0031] Furthermore, the present invention devises an uncoupling mat
of the type specified at the start which is characterised in that
the indentations have corner regions, the cross-section of the
indentations in at least some corner regions increasing towards the
first side, in particular constantly increasing, preferably from
the bottom of the corresponding indentation. Corner regions
configured in this way lead to air being able to escape well while
thin bed mortar is being applied to the first side of the plastic
layer of the uncoupling mat with an appropriate trowel, as a result
of which air inclusions and the formation of uncontrolled cavities
associated with the latter are able to be prevented, and good and
consistent filling of the indentations with thin bed mortar are
guaranteed.
[0032] According to a first version of the uncoupling mat according
to the invention the cavities cross one another and define a grid-
or net-like arrangement. In this way almost consistent and good
uncoupling is guaranteed in all directions.
[0033] Advantageously, the uncoupling mat in this version has 100
to 3000 indentations per square metre, as a result of which the
uncoupling function is also optimised.
[0034] According to a second version of the uncoupling mat
according to the invention the indentations cross one another and
define a grid- or net-like arrangement.
[0035] In this second version the uncoupling mat preferably has 100
to 3000 cavities per square metre, as a result of which the
uncoupling function is optimised.
[0036] In the second version the cavities can at least partially
have an annular cross-section. This means that additional recesses
are formed on the opposite side, as a result of which the bearing
capacity of an arrangement produced with the uncoupling mat is
improved.
[0037] According to one embodiment of the present invention the
indentations have a minimum width in the range of from 3 to 20 mm
and a maximum height in the range of from 2 to 20 mm.
[0038] Turning now the figures, FIGS. 1 to 5 show an uncoupling mat
1 according to an embodiment of the present invention which has, as
main components, a plastic layer 2 and a fleece or fabric 3, and
which can be provided in a sheet or a roll.
[0039] The plastic layer 2 is produced from film-like plastic and
has a substantially consistent thickness d which is normally in the
range between 0.4 and 1.0 mm. Accordingly, the plastic layer 2 is
extensible, i.e. it can be deformed manually. The plastic layer 2
is provided with structuring which on a first side 4, which in the
correctly laid state of the uncoupling mat 1 forms the upper side,
defines indentations 6 provided with undercuts 5, and on the
opposite second side 7 defines cavities 8 arranged between the
indentations 6, which cavities in the present case cross one
another and form a grid-like arrangement. The indentations 6
provided in a regular arrangement preferably have a minimum width
B.sub.min in the range of from 3 to 20 mm and a maximum height
H.sub.max in the range of from 2 to 8 mm, their number being in
particular 500 to 3000 per square metre. In this case the
indentations 6 are substantially cuboid in form, the undercuts 5
each being formed by a projection 9 which projects into the
indentation 6. However, it should be clear that the indentations 6
may also differ from the cuboid form, for example, as seen from
above, they may also be hexagonal or octagonal, cross-shaped or
circular in form. Likewise, the shape and number of the projections
9, and accordingly also of the undercuts 5 formed by the latter,
may vary. Thus, the side walls which delimit the indentations 6
laterally may also simply have a corresponding incline to the
vertical V (direction perpendicular to the bottom 11) in order to
form the undercuts 5. The cross-section of the indentations 6
increases constantly in the corner regions 10 from the bottom 11
towards the first side 4. In the present case this is achieved by
the inner edges defining the corner regions 10 being inclined
accordingly with respect to the vertical V. A plurality of
weakening zones 12 extend between the indentations 6, which
weakening zones extend continuously and preferably in a straight
line between opposing side edges of the plastic layer 2, in the
present case perpendicular to the latter and parallel to one
another. The weakening zones 12 are provided as grooves with a
substantially semi-circular cross-section. Basically, however, the
grooves may also have a cross-sectional form that differs from
this, such as for example the form of a semi-ellipse, a triangle or
the like. In the embodiment of the weakening zones 12 shown in FIG.
2, the thickness d is constant in relation to the thickness d of
the other plastic layer 2. However, it may also be smaller, as
shown by way of example in FIG. 4, as a result of which an
additional weakening effect is achieved. The weakening zones 12 are
spaced apart equally from one another, the distances preferably
being in the range of from 10 to 100 mm, in particular in the range
of from 10 to 50 mm. The weakening zones 12 may be formed here
between each row of indentations 6. Alternatively however, they may
also be provided only between every second or third row of
indentations 6, to give just one example. The distances between the
parallel weakening zones 12 in the longitudinal direction L and the
transverse direction Q of the uncoupling mat 1 may also be
different. Moreover, weakening zones 12 may also be formed only
transversely to the longitudinal direction L or only transversely
to the transverse direction Q.
[0040] The fleece or fabric 3 is connected securely to the second
side 7 of the plastic layer 2 and accordingly covers the cavities 8
thereof. Thus, the fleece or fabric 3 may be laminated onto the
second side 7 of the plastic layer 2, for example, or be adhered to
the latter. The fleece or fabric 3 comprises regularly arranged
through holes 13 with a cross-section in the range of from 0.5 to
1.0 mm.sup.2, in particular in the range of from 0.5 to 0.8
mm.sup.2.
[0041] The uncoupling mat 1 serves to uncouple a substrate 14 and a
slab covering 15 laid over the latter in terms of stress. In a
first step, as shown in FIG. 5, it is fastened to the substrate 14
using a thin bed mortar 16. The thin bed mortar 16 is mostly
applied to the substrate 14 here using a trowel and/or a toothed
trowel, whereupon the uncoupling mat 1 is positioned and pressed
onto the substrate. At this juncture the thin bed mortar grips in
the fleece or fabric 3, as a result of which a first fixing is
brought about. A fleece is advantageous in that it consists of a
plurality of small individual threads which also project outwards,
as a result of which a profound connection to the thin bed mortar
16 is achieved. In the case of a fabric, this should also have
projecting individual threads in the manner of a fleece so as to
also bring about the appropriate effect. By virtue of the chosen
cross-section of the through holes 13, the latter are sufficiently
large for the thin bed mortar 16 to penetrate the fleece or fabric
3 slightly, as a result of which further fixing is achieved by the
anchoring of the thin bed mortar 16 behind the fleece or fabric 3,
but they are also sufficiently small, and this reliably prevents
the cavities 8 of the uncoupling mat 1 from completely clogging
with thin bed mortar 16.
[0042] In a second step the slab covering 15, for example in the
form of tiles, is then laid over the plastic layer 2 of the
uncoupling mat 1, once again using thin bed mortar 16, the thin bed
mortar 16 anchoring in the indentations 6 provided with undercuts
5. When distributing the thin bed mortar 16 over the plastic layer
2 with a trowel and/or a toothed trowel, it is ensured by virtue of
the design of the corner regions 10 of the indentations 6 that any
air that is present in the indentations 6 can escape without any
problem, as a result of which the formation of cavities between the
uncoupling mat 1 and the slab covering 15 is suppressed, and
complete filling of the indentations 6 with thin bed mortar 16 is
also guaranteed.
[0043] If stresses now occur in the substrate 14, caused for
example by the remaining drying and curing process of the substrate
14, by the so-called settling of a construction, by temperature
changes due to different thermal expansion coefficients of the
materials used or the like, these stresses are thus absorbed and
compensated for by corresponding deformation of the uncoupling mat
1 so that they can not be transmitted to the slab covering 15. The
freedom of movement of the uncoupling mat 1 required for this is on
the one hand provided by the cavities 8 formed on the second side 7
of the plastic layer 2, which cavities allow movement of the thin
bed mortar stilts formed in the indentations 6 in the direction of
the cavities 8. On the other hand, the weakening zones 12 enable
expansion and/or compression of the plastic layer, in each case
respectively perpendicular to the direction of extension of the
weakening zones 12, as a result of which additional uncoupling is
provided.
[0044] FIGS. 6 to 8 show an uncoupling mat 1 according to a second
embodiment of the present invention which also has, as main
components, a plastic layer 2 and a fleece or fabric 3. The
uncoupling mat 1 according to the second embodiment only differs
from the previously described embodiment with regard to the
structuring of the plastic layer 2. In the present case the
structuring defines on the first side 4, which in the correctly
laid state of the uncoupling mat 1 forms the upper side,
indentations 6 provided with undercuts 5, which indentations are
made in the form of channels and form a grid-like arrangement. On
the opposite second side 7 the structuring defines cavities 8
arranged between the indentations 6, which cavities in this case
are in an octagonal annular form so that a recess 17 develops in
the middle of an annular cavity 8 on the first side 4. The
indentations 6 have a cross-section which is adapted to the
diameter of a cable 18, in particular a heating cable, such that
the cable 18 can be held, clamped in the indentations 6, as shown
by way of example in FIGS. 6 and 7. The weakening zones 12 extend
in the middle of the indentations 6 in the longitudinal and
transverse direction of the uncoupling mat 1, which weakening zones
in the present case are formed similarly to the weakening zone 12
shown in FIG. 2, only that they are curved upwards and not
downwards. It should be pointed out that the form of the
indentations 6 and cavities 8 may vary. Thus, the cavities may also
have a form that differs from an octagonal annular form, to give
just one example.
[0045] It should be clear that the embodiments described above only
serve as examples, and they are in no way to be understood to be
restrictive. In fact, changes and/or modifications are possible,
without straying from the scope of protection of the present
application which is defined by the attached claims. In particular,
individual features of the embodiments that are described may be
substituted.
LIST OF REFERENCE SIGNS
[0046] 1 uncoupling mat [0047] 2 plastic layer [0048] 3
fleece/fabric [0049] 4 first side [0050] 5 undercut [0051] 6
indentation [0052] 7 second side [0053] 8 cavity [0054] 9
projection [0055] 10 corner region [0056] 11 bottom [0057] 12
weakening zone [0058] 13 through hole [0059] 14 substrate [0060] 15
slab covering [0061] 16 thin bed mortar [0062] 17 recess [0063] 18
cable [0064] B.sub.min minimum width [0065] H.sub.max maximum
height [0066] d thickness [0067] V vertical [0068] L longitudinal
direction [0069] Q transverse direction
* * * * *