Note: Descriptions are shown in the official language in which they were submitted.
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RETAINING WALL SYSTEM
TECF~1ICAL FIELD
[0001] The invention relates to a retaining wall system of
blocks stacked together with interlocking dowels.
BACKGROUND OF THE ART
[0002] The invention relates to improvements in a retaining
wall system that is generally of the type described in United
States Patent No. 5,984,589, the disclosure of which is
incorporated by reference. Earth retaining walls are commonly
constructed of cast concrete blocks or stones which are stacked
in rows vertically upon each other. The finished surface of the
wall may have a batter angle where each row of stones is set
back or staggered a slight distance toward the retained earth to
produce a slanted wall face.
[0003] Many different systems of interlocking are used
between the stacked rows of stone in the prior art such as
interlocking tongue and groove systems. However, in the present
invention the system utilizes dowels in a receiving socket or
slot which project downwardly into a longitudinal groove in the
top surface of the underlying block. The dowels serve to locate
the blocks in position and anchor the layered rows of blocks
together to resist lateral pressure exerted on the retaining
wall by soil pressure, ground water pressure and superimposed
loadings. Examples of such retaining wall blocks are described
in United States Patent No. 5,984,589; 5,528,873; and 5,282,700,
which are hereby incorporated herein by reference. Such blocks
may have tapered sidewalls disposed at varying angles to the
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front face, the tapered sidewalls may not be arranged to abut
against one another depending on the wall's curvature, and may
not be readily aligned to produce a straight wall as a result.
[0004] The specific blocks of prior art U.S. Patent No.
5,984,589 include a single outwardly facing or presentation face
that has an irregular surface to present a broken stone finish
as opposed to a smooth cast surface. The broken stone or
irregular surface is produced by casting the stone in concrete
with a split line groove along which the block is split during
manufacture or during construction. Such blocks are trapezoidal
in shape to permit construction of wall configurations that are
curved, straight or double curved in S-shapes generally by
placing the blocks in the desired configuration with minimal
cutting and fitting.
[0005] The disadvantages of existing trapezoidal shape blocks
include a limited degree of curvature to which outside curves
can be formed due to the angle at which trapezoidal side walls
are positioned. To achieve a tighter curve, smaller blocks may
be used or the edges of the blocks may be trimmed. However,
trimming the edges of the blocks may also trim off the sockets
that receive dowels and so interferes with placement of the
interlocking dowels.
[0006] Conventional trapezoidal shape blocks have only one
finished or outward facing presentation face. Therefore to
build an inside curvature, the blocks are fanned apart and laid
with the rear end spaced apart thereby reducing the mass of the
wall and introducing the potential for moisture penetration or
in-growth of roots.
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[0007] Further when only one finished or outward facing
presentation face is used, and the tapered sidewalk are not at
a uniform angle relative to the finished or outward facing
presentation face, alignment and construction of a straight wall
requires more skill and attention than when rectangular blocks
are used for example.
[0008] A further disadvantage of the conventional trapezoidal
shape blocks is the limited design potential since blocks of
various widths may be laid in horizontal rows only.
[0009] Objects of the invention will be apparent from review
of the disclosure, drawings and description of the invention
below.
DISCLOSURE OF THE INVENTION
[00010) The invention provides a block, for constructing a
retaining wall of aligned rows of said blocks stacked with
interlocking dowels engaging adjacent blocks. The block has a
trapezoidal body with: parallel broad and narrow presentation
faces each having a width; opposing lateral side faces disposed
at a side angle relative to the presentation surface; and
opposing parallel top and bottom surfaces defining a block
thickness. A pair of parallel elongate grooves in the top
surface extends between the lateral side surfaces, each of the
grooves disposed equidistantly from one presentation face. A
number of locator sockets extending between said top and bottom
surface receive dowels to locate and arrest movement of the
stacked blocks.
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DESCRIPTION OF THE DRAWINGS
[00011) In order that the invention may be readily understood,
one embodiment of the invention is illustrated by way of example
in the accompanying drawings.
[0010] Figure 1 is a top perspective view of a trapezoidal
shaped block in accordance with the present invention showing
the broad presentation surface forward with dowels placed in the
two receiving sockets adjacent to the broad presentation
surface .
[0011] Figure 2 is a like perspective view of the same block
viewed from the narrow presentation face.
[0012] Figure 3 is a perspective view of a trapezoidal shaped
block without beveled top and bottom edges with the broad
presentation surface and dowels removed to better illustrate the
receiving sockets in hidden lines.
[0013] Figure 4 is a plan view showing an example row of
blocks having three different widths in a configuration which
can be used for constructing inside or outside curves.
[0014] Figure 5 is a plan view of the same three blocks shown
in Figure 4 but arranged in a straight line layout where the
triangular spaces between the blocks faces into the earth slope.
[0015] Figure 6 is a plan view showing an alternative
arrangement for straight line blocks and corner formation.
[0016] Figure 7 shows a straight line layout of blocks with
the subsequent row of blocks superimposed.
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[0017] Figure 8 is a sectional view along lines 8-8 of Figure
?.
[0018] Figure 9 is a sectional view along lines 9-9 of Figure
7.
[0019] Figure 10 is a top plan view of two trapezoidal shaped
blocks formed into a blank and showing the three parallel split
lines along which the blocks can be separated to reveal the
broad and narrow presentation faces for each of the two blocks.
[0020] Figure 11 is a like plan view of a blank which is
molded to form two corner pieces with split lines along which
two mutually perpendicular presentation faces are formed.
[0021] Figure 12 is a top perspective view of a corner block
produced from the blank of Figure 11, showing the two adjacent
presentation surfaces with receiving sockets open to the two
lateral side surfaces.
[0022] Figure 13 is a plan view of a molding arrangement
where blocks having three different widths are formed together
in two block pairs of blanks which are split into individual
blocks along the split lines to reveal the broad and narrow
presentation faces of each block.
[0023] Figure 14 is a top perspective view of a trapezoidal
shaped block produced from the blank shown at the top left of
Figure 13, with split line in the top surface to produce two
partial or corner blocks.
[0024] Figure 15 is an elevation view illustrating the means
by which the trapezoidal block can be positioned in a vertical
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position using a circular support engaged in a recess to produce
a vertical presentation surface.
(0025] Figure 16 is a like elevation view showing views of a
circular support and a second recess to produce a sloped or
battered presentation surface.
[0026] Figure 17 is a top perspective view of a block shown
in Figures 15-16 with recesses in one lateral side face.
[0027] Figure 18 is an elevation view of a wall assembly
showing the lay pattern which is achieved by stacking rows of
blocks having three different widths in a vertical pattern, with
a coping block on the top level.
(0028] Figure 19 is an alternative pattern which is achieved
by laying some of the blocks on edge, as in Figs. 15-16, whereas
the remaining blocks are laid horizontally.
[0029] Figure 20 is a further example of the pattern
achievable by laying blocks on edge in adjacent pairs.
[0030] Figure 21 is an alternative elevation design view
using the coping blocks which are one half the height of the
regular blocks to produce pattern variations.
(0031] Figure 22 is a further elevation example of a design
possible using half height coping blocks and blocks laid on edge
in combination with horizontally laid blocks.
[0032] Figure 23 is a perspective view of a coping block
having the same trapezoidal shape as blocks in Figs. 1-3 but
with reduced height and absence of grooves, sockets and slots.
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[0033] Further details of the invention and its advantages
will be apparent from the detailed description included below.
DETAINED DESCRIPTION OF PREFERRED EMBODIMENTS
[0034] Figures 1 to 3 show the general arrangement of a block
1 for constructing a retaining wall. Aligned rows of such
blocks 1 are stacked with interlocking dowels 2 engaging the
grooves 8 of a downwardly adj acent row of blocks 1 as indicated
in Figures 8-9 for example.
[0035] Each block 1 has a trapezoidal shaped body defined by
the broad presentation face 3 and a parallel narrow presentation
face 4, each having a width W, and opposing lateral side faces 5
disposed at a side angle a relative to the presentation surfaces
3 and 4. Opposing top surface 6 and bottom surface 7 define the
block thickness H.
[0036] A pair of parallel elongate grooves 8 are disposed in
the top surface 6 of the block 1 and extend between the lateral
side surfaces 5. Each of the grooves 8 are disposed
substantially equidistantly from one of the presentation faces 3
and 4. The positioning of the grooves 8 and equal distance from
the presentation faces 3 and 4 enables the blocks 1 to be
rotated 180° so that the builder can chose to expose the broad
presentation face 3 or the narrow presentation face 4 as desired
without interfering with the operation of the dowels 2 and
grooves 8 in interlocking the layered rows of blocks together.
[0037] For example, comparison between Figures 5 and 6
reveals that in Figure 5 the broad presentation faces 3 are
aligned in a straight line and the grooves 8 of all three blocks
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1 are aligned to receive the subsequent row of blocks 1 laid
upon them. In a like manner, rotation of the middle block in
Figure 6 does not interfere with placement of the dowels 2 since
the grooves 8 remain aligned in either position. The locator
sockets 9 extend the full height H between the top and bottom
surfaces 6 and 7 and receive the dowels 2 which extend
downwardly to engage the grooves 8 of the underlying layer of
blocks 1. The distance between the groove 8 and the broad
presentation face 3 is substantially equal to the distance
to between the groove 8 and the narrow presentation face 4, while
the side angle a (see Fig. 1) remains constant, so that 180°
rotation of the middle block in Figure 6 enables a straight wall
to be easily constructed with side walls of the blocks engaging
and both presentation faces 3, 4 presenting a finished wall
face.
[0038] As best seen in Figures 7-9, the selection of the
sockets 9 adj acent the broad presentation face 3 will result in
the stepped or slanted front wall surface shown in Figure 8,
while the selection of the sockets 9 adjacent the narrow
presentation face 4 will result in the vertical front wall
surface shown in Figure 9. In the illustrated embodiments, the
sockets 9 adjacent the broad presentation face 3 are offset
slightly forward of the associated groove 8 and this offset
dimension "x" establishes the step for each row of blocks when
the dowels 2 are inserted through the sockets 9 into the grooves
8 of the underlying row of blocks, as shown in Figs. 7 and 8.
However, the sockets 9 adjacent the narrow presentation face 4
are aligned centrally with the associated groove 8 and therefore
the interaction of the dowels 2 in the grooves 8 produces a
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vertically aligned and stacked row of blocks as shown in Figs. 7
and 9.
[0039] Referring to Figure 10, the trapezoidal block 1 of
Figures 1-3 is preferably constructed with both the broad
presentation face 3 and the narrow presentation face 4 formed
with irregular split or broken surfaces. The irregular split
surfaces are defined by vertically splitting a cast blank 10
along a broad split line 11 and a narrow split line 12 to expose
the broad presentation surface 3 and narrow presentation surface
4 respectively. The blocks 1 may be split along the split lines
11 and 12 during manufacture, with hydraulic press equipment for
example, after being removed from the mould but usually before
the concrete fully cures. Alternatively, split lines 11 and 12
may be molded, as illustrated, into the surface of the blocks 1
as a shallow groove. When the split lines 11 and 12 are molded,
the builder on the construction site, hammers a cold chisel
along the split lines 11 and 12 to separate the blocks 1 on the
broad split line 11 and to separate the discarded layers 13 from
the block 1 along the narrow split line 12. As seen in Figures
1 and 2, a chamfer on the top and bottom edges may be formed by
molding the split lines 11 and 12 as a triangular groove, which
adds a possible design feature. The alternative block 1 shown
in Figure 3 and the coping block 18 shown in Figure 19, show the
resulting edge without a chamfer, which may be produced by
splitting the blocks 1 and 18 during manufacture.
[0040] As best seen in Figures 6 and 10, the broad split line
11 and the narrow split line 12 are disposed equidistantly from
the nearest associated elongate groove 8. As mentioned above
the equidistance spacing is advantageous in that the broad
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presentation face 3 and narrow presentation face 4 can be both
utilized by rotating the block 1 180° to achieve various
configurations without detrimentally affecting the location of
the grooves 8 into which the dowels 2 are inserting to interlock
the overlying stacked layer of blocks 1.
[0041] Also, as best seen in the example of Figure 10, the
sockets 9 in the embodiment shown are shown cylindrical in shape
to engage with the cylindrical dowels 2. Different shapes of
sockets 9 and dowels 2 are possible. In order to enable
trimming of the lateral side faces 5 with a concrete circular
saw for example, the sockets 9 are positioned inward from the
lateral side faces 5 by a substantial distance "T", for example,
1.5 inches. The locator sockets 9 advantageously communicate
with a lateral slot 14 which creates a keyhole shape with the
slot 14 extending to the adjacent lateral side surface 5. This
configuration of socket 9 and lateral slot 14 simplifies the
construction of concrete molds and removal of the cast blanks 10
from the molds. By configuring the sockets 9 open to the
lateral side faces 5 via the slots 14 the sockets 9 may be
formed completely during the forming of the block 1 in a single
operation. For example, the block forming mold can have side
walls that include lateral protrusions or removable inserts to
form the slots 14 and sockets 9. The slot 14 has a length "T"
defined between the locator socket 9 and the adjacent lateral
side face 5 which defines a maximum lateral block trimming
allowance "T" such that the lateral edge can be trimmed without
cutting into the socket 9 and interfering with the operation of
the sockets 9 and the dowels 2.
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[0042] As indicated in Figures 10 and 13 it is advantageous
in the construction and in the manufacture of blocks 1 that the
side angle a at which the lateral side faces 5 are oriented
relative to the broad presentation face and narrow presentation
face 4 is a standard consistent angle. It has been found by
experience that an acceptable angle is 7.5° from perpendicular
resulting in a side angle a between 82.5° and 97.5°. A narrower
range of angle a will result in a block 1 that is more
rectangular in shape and therefore cannot accommodate inside and
outside curvatures as readily and a larger angular variation
will result in a more triangular shaped block which accommodates
curvature more readily however requires a larger number of
smaller sized blocks to be used during construction.
[0043] Figure 13 shows three different sizes of blocks formed
from nested blanks 10. For example, 10 inch blocks 15 are
nested with 12.5 inch blocks 16 which are also nested with 15
inch blocks 17 in a compact rectangular molded shape.
Construction of retaining walls with some variations in the
sizes of blocks 15, 16 and 17 is desirable to prevent a
monotonous finished wall appearance. The coping blocks 18 (see
Figure 23) which are laid to finish the top of a wall usually
have a lip or slight overhang but do not include grooves 8,
sockets 9 or lateral slots 14. Coping blocks 18 are formed
simply of a solid layer of the same trapezoidal shapes shown in
Figure 13 with broad and narrow split lines 11 and 12. Coping
blocks 18 are thinner and in the embodiment illustrated in
Figure 21-23, the coping blocks 18 are of height equal to one
half the height H of the other blocks 15, 16 and 17. The coping
block 18 as shown in Figure 23 includes a trapezoidal body with
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broad and narrow presentation faces 3 and 4, opposing lateral
side faces 5 disposed at the same side angle a relative to the
presentation surfaces, and has opposing top and bottom surfaces
6 and 7 defining a thickness that is preferably one half the
thickness of the other blocks 15, 16 and 17.
[0044] The retaining wall system also includes a corner block
19, shown in Figures 11-12 and installed in Figure 6. Split
lines 20 and 21 define mutually perpendicular presentation faces
3 and 4, side faces 5 are mutually adjacent, and one side face 5
is disposed at the side angle a relative to one of the
presentation surfaces 3. Opposing top and bottom parallel
surfaces 6 and 7 define the corner block thickness H which is
the same as the thickness for blocks 15, 16 and 17. Left and
right corner blocks 19 are formed together, then split along
split lines 20 and 21 to create mirror image configurations.
The grooves 8 in the corner blocks 19 do not extend the full
length of the corner blocks 19, to preserve the uniform
appearance of the full height of the presentation faces 3 and 4
and since the position of the interlocking of dowels 2 does not
require the grooves 8 to extend all the way along the length of
the block 19. Sockets 9 and slots 14 are provided on the two
side faces 5 which when constructed in the outside corner of a
wall, are hidden from view. The relative positions of the
sockets 9 in the corner block 19 are identical to such sockets
in the other blocks, namely to produce a vertical stacking of
blocks or alternatively a stepped or slanted finished wall face
as illustrated in Figures 9 and 8 respectively. Of course in
the case of the corner block 19, the builder has the option of
selecting a vertical or a stepped wall face on each of the
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mutually perpendicular presentation faces 3 and 4, independently
of each other (i.e.: both sides vertical, both sides stepped, or
one side stepped and one side vertical depending on which two of
the four sockets 9 are selected).
[0045] Referring to Figures 15-17, edge laid blocks 22 may be
laid on edge with the top and bottom surfaces 6 and 7 positioned
substantially vertically. In Figures 15 and 16, a horizontal
reference line is indicated. In Figure 15, the batter angle
achieved is 90° between the broad presentation surface 3 and a
horizontal plane 23 representing the top surface 6 of a footing
or underlying row of blocks 1. Two recesses 24 are formed in
the lateral side face 5 in order to position the broad
presentation face 3 at a batter angle i3 of 90° in Figure 15 and
a batter angle f~ of 84° in Figure 16 by inserting a cylindrical
support 25 into the recesses 24. To minimize the number of
components required for the retaining wall system, the supports
and dowels 2 can be formed of the same cylindrical shape.
Different shapes of supports 25 and dowels 2 are within the
contemplation of the invention.
20 [0046] Turning to the patterns shown in Figures 118 through
22, different wall lay patterns are possible as a result of the
different relative sizes of the blocks 15, 16 and 17, coping
blocks 18, and corner blocks 19 and the use of some blocks as
edge laid blocks 22.
25 [0047] In the first example shown in Figure 18, rows of equal
thickness H are laid horizontally and stacked upon each other
with the top layer being a coping block 18 layer of one half the
height of the remaining blocks 15, 16, 17 in the retaining wall.
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Some variety in the appearance is providing by using different
widths W of blocks which in the example provided are 10 inch
blocks 15, 12.5 inch blocks 16 and 15 inch blocks 17. As shown
in Figure 13, it is preferably to form blocks of different sizes
nested together in a standard sized pallet for use in a concrete
molding machine. For this reason, the three different sizes 15,
16 and 17 of blocks are nested together in a compact mold
configuration. In a laying the blocks as well, as shown in
Figure 14 for example, an equal number of all three sizes 15, 16
and 17 are utilized to provide visual variety and as well to use
the same proportion of each block 15, 16 and 17 during
manufacture and installation. Of course, when features such as
stairs or corners are necessary, cutting of the stones is
possible with a chisel or saw as required. As indicated in
Figure 6, to form a corner in the wall, it may be necessary to
trim edges along cut line 26 for example. Since the dowels 2
and sockets 9 are spaced inwardly by the lateral slot 14, minor
trimming of the edges along cut line 26 does not interfere with
the operation of the dowels 2.
[0048] Turning to Figure 19, a degree of variety in pattern
design is provided by introducing edge laid blocks 22. In the
example shown, the height H of all blocks is equal, such as 5
inches. Therefore, the edge laid blocks 22 in the example
Figure 15 are the 10 inch blocks 15 so that their vertical
extent is equal to exactly twice the height H of the other
blocks 15, 16, 17 laid horizontally. Of course, further variety
can be achieved by using the 15 inch blocks 17 as edge laid
blocks 22 and the vertical extent of the edge laid block 22 in
such case would be three times the height of the horizontally
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laid blocks. In the examples shown however, all the edge laid
blocks 22 are the 10 inch blocks 15. To maintain the same
proportion of 10, 12.5 and 15 inch blocks (15, 16 and 17) most
of the horizontal laid blocks are the larger 12.5 and 15 inch
blocks 16 and 17.
[0049] In the pattern shown in Figure 20, edge laid blocks 22
are positioned in pairs to provide further pattern
differentiation. As will be apparent to those skilled in the
art, since in the example shown (Figure 13) the number of
different sized blocks 15, 16 and 17 are equal, it is more
convenient to design laying patterns where an equal number of
the three different size blocks are used in the final wall
assembly.
[0050] Figure 21 shows further variation where edge laid
blocks 22 are used singly and further visual variation is
provided by using coping blocks 18. In the example illustrated
the coping blocks 18 have a height H which is exactly one half
the heights H of the remaining blocks 15, 16, 17, 22. In this
manner narrow bands of coping blocks 18 break up the appearance
of the finished wall. As will be apparent from Figure 23, the
coping blocks 18 may have the same variety of sizes namely, 10
inch coping blocks, 12.5 inch coping blocks and 15 inch.
[0051] In the final example shown in Figure 22, edge laid
blocks 22 are used and the coping blocks 18 are provided in
double layers to provide further visual variations.
[0052] The relative dimensions of the blocks stated
mathematically is: D is a selected dimension (2.5 or 5.0
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inches) ; the block height H is defined as H - Dn; and the width
W of at least one of the broad and narrow presentation surfaces
is defined as W - Dn, where n is an integer. Therefore all
relevant dimensions are multiples of 2.5 inches. It will be
understood that any selected dimension or multiple thereof can
be used if desired.
[0053] An advantage of the invention is apparent in the
construction of seat walls or stone fences. In such an
application, the wall is constructed of a single wythe of blocks
1 stacked to a selected height and capped with a row of coping
stones 19. In contrast, a retaining wall has aggregate and soil
in contact with one side of the wall (Figures 8 and 9) and
therefore the visual appeal and appearance of the hidden side of
the wall is of little consequence. Since the blocks 1 of the
present invention have two presentation faces 3 and 4, seat
walls or stone fences can be constructed with two exposed sides
using the arrangements of blocks shown for example in Figures 4
and 6 for curved and straight walls respectively. The ends of
the seat wall or stone fence can also have a finished roughened
presentation face as follows.
[0054] With reference to Figures 13-14, the block 17 in the
top left corner of Fig. 13 is shown with an optional split line
27 molded into the top surface of the block 17 as a shallow
groove. By splitting the blocks 17 along this split line 27,
the resulting partial stones 28, 29 have three broken
presentation faces, all arranged vertically. The partial blocks
28, 29 therefore can be used at the ends of such seat walls or
stone fences to present a finished broken surface on the
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vertical exposed ends as well as the two vertical sides of the
wall.
[0055] Although the above description relates to a specific
preferred embodiment as presently contemplated by the inventor,
it will be understood that the invention in its broad aspect
includes mechanical and functional equivalents of the elements
described herein.
